What is "Brainwave Entrainment"?
Here is a very brief explanation:
Brainwave Entrainment (BWE) is a process by which a rythmic stimulus such as beats or pulses can cause the brain's own brainwaves to match the same frequency as the external source. There are four standard brainwave states: beta, alpha, theta, and delta. Most bwe falls into one of these states. Depending on the frequency, we can help bring the brain into a more receptive state for learning, studying, meditation, hypnosis, and everything in between. Please see What Is Brainwave Entrainment? for a more thorough explanation.
I thought all brainwave entraiment required the use of headphones, but many of your product descriptions state that headphones aren't required. Can you explain this?
Of course. There is a lot of misinformation out there; unfortunately much of it is deliberate, for marketing purposes. Binaural beats, a form of brainwave entrainment, is the only technique that requires headphones, due to how the signals are processed (see next question below). Most of our products use a superior technology that does not require the use of headphones. However, as many of our products utilize 3D AuralScape™ technology, headphones are recommended, as 3D AuralScapes™ rely on how the brain processes incoming stimuli. But again, headphones are recommended, but not required, unless otherwise stated.
Another company's website stated that they use binaural beats but then claim that headphones are not needed.
Again, another marketing ploy (or out right lie, if you will). Binaural Beats require headphones, otherwise they do not exist, plain and simple. Just like with monaural beats, when two seperate tones are played, they combine to form the difference of the two beats (i.e. one tone is 300hz, the other is 310hz, the difference being 10, resulting in a 10 hertz frequency in the brain), however with binaural beats they are played directly into the ear, while monaural beats combine in the air before reaching the brain. Playing binaural beats without headphones is physically impossible; before reaching your ears the beats become monaural beats. While this can technically still lead to entrainment, unless the session was designed for monaural beats it won't likey be very effective. In any case there are other superior brainwave entrainment technologies available. Any claims to be able to utilize binaural beats without headphones is simply false advertising.
I recently bought a hypnosis product from another company and I could not hear any of the binaural beats, and they claimed it wasn't necessary to hear them for it to be effective.
Wrong, wrong, and umm...wrong. To put it very simply: your brain must hear the beats in order to elicit a cortical response (in other words, you must be able to clearly hear the beat/pulse pattern in order for your brain to sychronize, or match the pattern it is hearing. This is a standard law of neuralphysics. (On a side note, binaural beats are difficult to hear in the first place, usually being around 3 decibels, or about 1/10th the sound of a whisper). 
During extensive marketing research, we have tested many of our competitors' products, including those that claim you do not need to hear the beats to be effective. We had subjects listen to such products in a controlled environment while monitored by a state-of-the-art multi-channel EEG (Electroencephalography, a sophisticated medical device that measures brainwave activity) and found as we expected, that they often did not create the change in brainwave activity as advertised. All Nirvanic Mind™ products go through a thorough quality assurance, including the use of EEGs to ensure the products perform as designed.
What is Audiostrobe®?
Audiostrobe® is a patented visual brainwave entrainment technology invented by Andrzej Slawinski. It works by sending short inaudible pulses along a cable running from a sound source such as a cd player to a set of light goggles which results in a series of flashes that behave just like beats or pulses in creating change in the user's brainwave state. It is designed to be used in conjunction with audible entrainment such as binaural beats, but can be used alone as well. 
Audiostrobe® is usually only found built into light/sound machines,  however we have all Nirvanic Mind™ products encoded with Audiostrobe® and include it by default for no extra charge in all customized sessions. The use of visual stimuli along with beats/pulses can greatly enhance the entrainment effect, and some people enjoy visual stimuli all by itself. We highly recommend purchasing a light/sound machine for added entrainment value as well as for dealing with issues such as seasonal affective disorder and jetlag. The Procyon AVS from Mindplace is a peronal favorite.
What is 3D AuralScape™ technology?
3D AuralScape™ is a proprietary technology created by Nirvanic Mind™ which is used in most of our products. Rather than simply explain what it is, click 3D AuralScapes™ to experience it for yourself.
Can I have a CD of any product shipped to me?
In an effort to save you both time and money, we do not currently offer any product in any physical form; all products are made available as an immediate digital download in mp3 format. The process of CD stamping/printing along with the cost of shipping would increase the cost of our products significantly. Also, most people today use portable music devices such as Ipods or smartphones to play their digital music. If you prefer to have your session on a CD, that can be easily accomplished by you at home by burning the mp3 file(s) to CD from your home PC. 
After I have purchased my product(s), how will I receive them?
Once the transaction has been completed successfully, you will receive a confirmation email with the download links for the products purchased. The products are packaged in zip format, which may need to be unzipped (uncompressed) by your operating system before you can use them. Most newer operating systems come with unzipping utilities; however you may download free unzipping utilities such as Winzip or WinRAR.
What is your return policy?
While we are very confident you will find our products to be the best brainwave entrainment sessions available, we understand you may have reasons for wanting a refund. We have a 60 day return policy. Our policy is that you must try the product for a minimum of 30 days before we perform a return, to ensure that you give the session adequate time to work. Sometimes it may take days or a week or so before you notice a difference. Everyone responds differently. If after 30 days you are still not satisfied with your product, we will most certainly perform a refund for you. No refunds on completed customized sessions and a 50% surcharge is applied to any cancelled customized session once work has begun. No refunds on distance healing sessions; any session cancelled later than 2 hours prior its scheduled time will incur a 50% surcharge. For more information, please see the Terms And Conditions link at the bottom of the page and the EXCLUSIVE: Customize Your Own Brainwave Entrainment Sessions and Energy Healing Sessions pages.