I just bought a Suzuki Across... being a chick's bike and all, slow but very light, so really easy to learn on... got her for just under 4k with good mileage, immaculate paint job (which i've now deflowered) jacket and a spare helmet. Got told over the weekend that the Across's are the crappest learners bike, but I'm not having too many dramas, apart from having to clutch start it when i left the boot open - yes, there is a boot or helmet holder type thing, so good for my handbag, lip gloss and stuff...
I've already dropped her a few times, so don't spend too much money on your first bike, especially if you need a valium after putting even a tiny scratch on her.
Another option is the ZZR250 and I'm partial to the GPX250... happy riding, see you on the roads soon!! If you do the pre-learners course at Clyde, pray for Frank as your instructor as the other guy is mean!!! And screams if you give his bikes a bit... but it's easy as a hooker on William Street and if they passed me, they'll pass you!
Good luck son!! Once you get it, you won't want to get off... and you'll be contemplating upgrading after about a week. I'm already thinking of an R6... I'm off to go for another ride!
