All of the above is good advice and I too advocate buying good quality stuff that will last. However, you don't need to start expensive and hopefully you'll get the opportunity to try out different tools as you gain experience and build on that. I actually use
1) Very cheap (my preference) small (150-160mm) & larger cable cutters.
2) LED Lenser AAA battery head torch (not the brightest model, but the batteries last longer) invaluable.
3) Quality VDE Screwdrivers (Bahco etc...mid-range are fine).
4)12v, 18v, 240v Bosch blue...others are also good but I have experience of dropping these on occasions and leaving out in the rain (not 240v)...they take it everytime.
5) "Large" folding plastic step 390-400mm (H) from hobbycraft (small footprint for domestic ceiling work) + 5 tread fibreglass steps
6) Quality drill bits if used everyday (forget cheap large sets).
7) 10mm2 G/Y single cable 200mm long. 90 deg bend To check for obstructions for D/Light positioning or location of joists/pipes.
8) Knee pads
9) Duck tape.
10) vaseline
...I think i need to stop now....need fud