I can tell you what I WON'T spend (more like could never): $10,000 for a bike like the pros. Like Tulip, I have a varied range from $7 mixte I found on craigslist to a higher dollar tri bike. I like them all equally.
When I visited my brother last summer in Colorado, he asked me what my bike cost. I tried to downplay it, but after much persistence I told him. His jaw dropped. I told him it was the same amount of money that some people spend on Starbucks 3-4 days a week for an entire year, and at least I have a bike to show for it at the end of the year. If you're not a cyclist- you just don't "'get it."