First off, stop misusing the word "friend". This person saw you as a "mark" and manipulated you into forking over 3k. Sounds like you didn't know them very well, or were trying to impress them with the hopes they might sleep with you or have a relationship. Anyways...
No, you won't go to jail or be criminally prosecuted for these loans. You will, however, have them hounding you for payment. Also, since you wrote checks, your bank account is going to be really SCREWED up due to all the NSF fees you are going to get from them depositing the checks or running them as a debit in order to get their money when you cannot show up with the full amount to pay off the original loan and interest and then re write the loan which just starts the whole cycle over. Since they will be screwing up your bank account, you are going to now risk losing that because your bank is only going to allow you to be in the red for maybe 30 to 45 days before they just close your account due to NSF and negative balances and send your info to ChexSystems. This will prevent you from being able to open a new bank account for 5 years. You would also still owe the bank the money for all the bounced check fees these payday lenders are going to cause you. Closing your bank account won't help either to avoid them putting the checks through. Your bank will just slap you with fees for not leaving enough in the account for incidental things that may come through afterwards.
Time to find a 2nd job so you can put all that money towards this payday loan fiasco. Also, if this person was such a "friend" how come you don't know any of their family or friends so you can find out where they are? Do you know their real name? Can you Google and find them on FaceBook or something so you can figure out where they absconded to so you can take them to small claims court and sue them? LOL Thing is, you would have to prove that they agreed to pay you back and if it looks like it was a case of you being fond of the person it may be seen as you were giving a gift.
At any rate, no, you won't go to jail.
These people here telling you they are going to "garnish" your paycheck need to go back a step. The payday lender at worst would send your account to a collection agency who would then pester you daily. They CAN choose to sue you. The above answer is WRONG when they state that judges will not award the money you owe to a payday lender! You signed a binding contract that is about 3 to 5 pages long. There is a section in that contract that talks about arbitration and going to court if you do not pay. READ that part! That is what they can do to you. They would need to WIN a judgment and a court order to garnish your wages, place liens on property or levy your bank account.