To LEARN on, take most any "beginner riders course". They will teach you how to ride from the perspective of never having ridden at all, and have most folks riding within a days class. Riding well enough to take on residential streets and short commutes. And they will provide the bike (typically something in the 250 cc range) to learn on, and occasionally dump.There's a bunch of nice bikes in this thread!
Not to derail too much, but as a kid who's full of pIss and vinegar would anyone recommend a good starter bike?
Your "first bike" should usually be looked upon as just that. Harley had a deal where they were selling 1200 cc Nightster Sportsters cheap, and offering a full value "trade up" in a year on a new full sized bike. You can still find 1 and 2 year old low mile Nightsters for around $5-7K (US).
I don't know tons about sport bikes, but anything from the major Jap makers in the 650-700 range is typically a nice starter bike for someone with brains, a bit of experience, and knows how to find his/her limitations intelligently. You can always find local "track days", to increase your limitations and learn your handling skills safely and in a controlled environment.