praveen
your budget of 500 USD is quite unrealistic... as jeff pointed out
for ex. 500 USD is body + 18-55mm lens only. the 500 USD equiv price is india would be much higher I expect atleast 50-100$.
Rest aside, u need eneloops (rechargeabe batteries), a camera bag. It will push your price by another 2-3k Rs.
I got k-x for 560 odd with 18-55 and 50-200 kit lens. eneloops 18$ bag 50$. couple of manual prime lenses from ebay 100$ in all. pentax forum site support 10$
i still have to buy a better memory card, may be a polarizer or 2, lens hood, and yes tripod later. and mebbe another cheapo manual lens.... so i think it burned me close to 800$.
im frantically buying stuff that I may use much later because im moving back to chennai soon.
However, basic essentials body, kit lens, bag, cards, memory card and eneloops. should be close to 650$-700$. again this is US price.
My best advise would be to request someone coming back from US to get you the stuff.