Want a Good Entry Level Bike

I am an absolute beginner, and have just started spinning classes, etc to lose weight and train for a sprint level tri in 2006. I have about 70 pounds to lose, and I want to start riding with a local group here in south Texas, but I don't have a bike.

I would like a good entry level bike, no more than a year or two old. Have looked at a Raleigh grand sport (2004 model) at the local bike shop for around $450-$500, but I don't know enough about these bikes to know what is best.

If someone has any input, I'd appreciate it. If someone has a good bike at a good price that can be easily shipped to Brownsville, texas, please post here with info and price, and/or email me at [email protected]

I am 6 feet tall, male, and weight about 280. Not even sure what size bike would be best, so any experts out there can help with that too.

Thanks,

Brandt