Indian Phone & SIM (Bangalore)

I know I can get a SIM, but am I able to purchase a phone when I arrive? AT&T in the US will not unlock my phone without making me cancel my service for $325 USD. I don't want to cancel my service because I have 3 other lines and I'll be back in 6 months. Surely I can get a phone to use in India cheaper than that! I'm so frustrated! Thanks in advance for any advice!