Here's where I stand.
Get a semi decent cordless one for most jobs. I have a three DeWalts (DW907, an XRPhardbastid and one in between), one is Nicad, the Li-on and both do a good job but are useless at masonary even though they have metal gearboxes and hammer action. I use them mainly for wood, metal and screwing. I also have an 12v Atlas Copco drill which was sturdier as you'd expect from someone like AC. But it's ancient and the batteries have died.
For serious drilling I have a cheap and nasty Wickes own brand hammer drill which cost £25. I don't care if it dies but it never does, just like Gattapardo's Tesco Drill, though we did manage to make his Bosch mains one release some magic smoke.
So yeah spend £80-120 on a nice battery drill, DeWalt, Panasonic, Hitachi, AEG, Makita etc all make lovely drills. If I was starting over, I'd go with Hitachi or Makita. If you stick to the same rough range batteries are interchangeable. Make sure you get at least two batteries. Lion is what you want and 14.4v+. 2ah batteries is the lowest worth getting. Try and make sure you get one with a metal gearbox and one where the bushes are easy to replace.
And then spend £30 on a cheapo mains drill to abuse. CPC usually have some good deals on Bosch for about £35. Otherwise their own brand starts about £20.