My brother in law has a web shop, its still being developed and cost a fair bit to have done, but he has a lot of stock options available (basically its selling professional automotive tools to non trade customers). His old site worked on the principles of "here's what I do, tell me what you need" but only listed limited products, and as such didn't work well.
If you're just selling bearing kits, then a page with a list is adequate, as most people will know what they need, google it and buy from the cheapest/best dealer. A data base system is fairly straight forward, so if you had a range of bearings of different qualities, or perhaps one bike required different sets for different parts, a drop down box with "select your bike" which then led to a page listing (and showing cos everyone loves pictures) the products for that particular bike, that way, if I come looking for basic bearings for, say a 2004 Orange Patriot, I can find what I need quickly, but I can also be shown better products that might tempt me to spend more with you!
If you are also offering services, then you need to be more descriptive, and essentially have good web based communication. Perhaps a fixed form with
Type of bike:
Brief details of problems:
What you want doing:
MAybe I'm shy but I don't like being telephoned following submission of a form/email. I work shifts and quite often send forms late at night, so prefer to deal by email, but that said, if phoning customers is an option, make it clear that that is what you are going to do. The nature of servicing frames might require some conversation/ discussion so its good to build client trust. Kinda like my VW mechanic, he tells me whats wrong with my van and how he's going to fix it, rather than just saying its broken, it needs fixing.
Perhaps the hardest part is deciding on your web image. As a one man band, you could push the "Kaesae's old time bearing shop" image, make it clear that you're a guy on his own doing what he loves for money, or you can go for "globalhypermegacorp" faceless branding, which can imply more professionalism (in some peoples opinion) but takes out that personal touch. Think of it as dealing with CRC v's dealing with On-One in the Brant era, when Brant was on here all the time and all those "what size 456 should I get" questions were answered by the guy who designed it!
And finally, advertising. There are loads of people selling loads of shat on the internet. Google is in fact not your friend, don't rely on search engines for custom. Also perhaps avoid sneaky forum advertising, people aren't wild keen on that! I'm sure advertising on here isn't that expensive (just don't make it flash!) and could be a god way to communicate with the kind of clientele who service their own bikes rather than going to halfrauds etc.
Good luck with it!