Look on the bright side. Now house prices are not being artificially held higher by that incentive. Prices should drop that much and more. Pay off your debt, get your fico score up. Then in a year or 2 find almost certainly better prices and buy then.
The best answer hurts the most. Pretend that you are 2x poorer than you really are. Stop doing things that cost money. No cable tv, no coffee you do not make. No doughnuts. Eat the cheapest food you can buy. Buy anything you need for CASH only. Forget credit exists and start shopping at goodwill. Lots of ok stuff at cheap prices. In time you will be surprised how much better off your fico score is and how much better your back pocket feels. If you have any credit cards talk to a non-profit credit counseling agency. Pay off the highest interest rate one first, and then the next highest until you owe nothing. Just doing that will help your score a lot. Plus you have to save for a down payment. consider it a 5 year plan. If you do things right in 5 years you should be a lot better off financially and with fico score.
It is quite obvious that the other responders have already corrected your vision of the ending date for the tax credit program, so I won't "pile on."
What I would like to suggest however, is this: because the end date for the tax credit program was not clear to you, it tells me that you are apparently not connected with a great local real estate agent in Philadelphia County. Any agent worth his/her salt would have informed you very clearly of the deadline you must meet in order to grab the $8000 (maximum) from Uncle Sam.
So may I suggest that you find an agent to represent you asap. Ask your friends and family if they can recommend an aent who works in the areas where you are interested in buying. Then make an appointment to meet with at least 2 to 3 of those recommended agents. Choose the one who makes you most comfortable, and who answers your questions with knowledge AND with respect. Then, and only then, can you take the next steps to learn what is possible for you in terms of purchase price points and mortgage programs. Your new agent can connect you to an experienced mortgage broker, your second-best friend!
I would build your credit up more and more. There are some programs out there but typically you will need 3.5% down to qualify for a FHA mortgage and around a 620 credit score.