Ok, i'll try and make this as clear as possible, lord know it was hell for me to figure it out.
I PreOrdered my copy of Destiny through PSN on my PS3. I finally did receive the email from Sony (which I was at first trying to view through my smart phone, then I tried viewing it through my Playstation3), but it contained 2 PS4 codes, and when I tried to use the "add to library" link contained in the email above the codes, the site I was brought to by said link (a PSN site, it was official) told me the Beta for both PS3 and PS4 was not available.
Well I've been fiddling around all night and I got it to work. I opened up the email account tied to my PSN account on an actual computer. I clicked the link "add to library" and was brought to the same site as before, only this time the PS3 Beta was available. I clicked on it, and added it to my shopping cart. I then proceeded to checkout and completed the transaction (at a cost of 0 dollars, so don't worry. It will even say 0 dollars).
After that, I went back to my Playstation, restarted it (just in case), and once my system logged my account in, I went to Account Management, and from there I went to Download List, and there was the Beta, ready for download. I selected Download, set it up to download in the background, and last I checked the download was under way.
Hopefully this will help some of the PS3 users like myself, who purchased the game on their PS3 through PSN.
Now let me say this. The fact that there is no direct support from Bungie for PS3 users is shameful, and I'm sorry, posting on forums and hoping to receive help does not count (I am more than willing to put my foot in my mouth and apologize if I have missed something), and just as shameful is the fact that Sony and PSN have absolutely no idea what is going on at this time, and can offer absolutely 0 help on the matter.
I will apologize to Bungie. Their official sites claiming PS3 users do not need a Beta code if the game was preordered on the PS3 system through PSN are indeed correct.
Sony, on the other hand (who I've spent about 6 hours on the phone with today, and even got them to offer me a full refund of the price of Destiny, though I didn't take it obviously) has lost a ton of respect from me in my eyes. They informed me, beyond any doubt, that I would need a Beta code, no matter what, and when I received the email containing the codes FROM SONY ITSELF, they told me there was nothing they could do about the fact I received PS4 codes when I needed PS3 codes. They said and I quote "we don't just have extra codes lying around". Which would be fine, if they actually knew how to get the download up and running, which they don't. Unless you can remain civil while being angry, unless you can voice your issues clearly and intelligently, and unless you want your money refunded and don't want to play the Destiny Beta, DO NOT CONTACT SONY, YOU WILL BE WASTING YOUR TIME, AS THEY HAVE NO CLUE WHAT IS GOING ON.
Anyway, this has been an extremely rocky start, I think things have been way more complicated than they needed to be, and it is apparent that there has been almost 0 collaboration between Bungie and Sony. Hopefully the future holds more positive situations, for players on all systems, and for Bungie and Sony as well.
Also, a quick shout out to Major Enigma. I was totally caught of guard by his kindness and sincerity, and he was 1 million times more helpful than Sony or Bungie. Definitely a rare quality in this internet day and age. Thank you again so much Major, and good luck to everyone out there, I hope this helps you guys.