Hi, I am on H1-B visa from Dec 2006 to Present so for 2007 I will file resident tax return.. Please let me know which form I should use to file my return. I am single and work for a consulting company in TX.

For you federal tax return you have to use 1040 or 1040EZ, same forms you used for your 2006 tax return, also you'll have to file, depending on your state of residency, State Tax return as well.

For 2007, you will file 1040EZ or 1040A or 1040.
For 2006, since you did not provide your status before Dec 2006, I am not sure if you can file resident tax return.