I am working on H1B and planning on requesting the $7500 (or $15000) tax credit for first time home owners. Will be filing jointly, but my wife has ITIN. Am I eligible to get this credit?

Resident aliens even with ITIN are eligible.
This credit is available for first time home buyers and those who did not own home in last three years. It is in fact interest free loan of up to $7,500.
Your U.S. Tax Return: First-Time Homebuyer Credit

Thanks Makata for your answer and links.