You should try to find a house prior to the end of the 7500 tax credit so you can take advantage of it. I believe that would mean closing before the end of June. Search the site for more info on the tax credit if you are unaware of it.
Also, generally, late spring and summer are the most expensive time and busiest time for house hunting/buying and prices will always fluctuate upwards (in regards to other times of the year) during these times.
Your scores are fine for FHA, the only issue would be DTI and for that we would need to know what price point you are looking at and what taxes, etc would be...Also, how much is your student loan payment.
Anyways, with FHA you only need 3.5% down and waiting a few month to get extra money down may not be best if that means you pay a couple thousand more for the home as well due to summer market conditions verses winter/early spring. Also, you could take the tax cresit next year and apply it to your mortgage, your student loans, home renovations, or whatever.
