Poker Software: When to get it?

I've only just gone 18 but I've been playing since I was 10 so although I know the game well, I've not had much experience with money games.

I've played online a lot in freerolls, SNGs and money games if I can win enough and I managed to get a few days here and there of grinding before I tilt and lose it all.

But I was thinking about taking around £100 and setting myself some realistic goals and taking grinding a lot more seriously and seeing how it goes.

I've read into it a bit and there's mixed opinions so I was looking for your opinion on it. Some books mentioned getting a bigger screen/dual screen when it comes to playing a lot of tables at once, so I hooked my 32" TV up so I've got that and my 22" monitor - more than enough space!

Any advice?