The Garden Restaurant does really nice indian food. The downstairs is all veggie, and upstairs serves meat dishes. I've tried a lot of the indian food available in Qatar. The expensive restaurants in hotels do very nice food indeed, but some of the takeaways do food that tastes very mass-produced. Anyway, when I tried the Garden I was very impressed.

If you're on the corniche heading towards west bay area, turn left before the Emiri Diwan (palace), and then right (so that you're going behind it), then turn left at the next set of light (where the road varies from 2-3 lanes for no apparent reason). You'll be very close to the restaurant then. Park up and ask.