I guess my original question wasn't very clear. We are looking to purchase CAD 3D models of aircraft fasteners so we don't have to model them ourselves. We want to see if it's cheaper to buy a CD library rather than pay one of our employees to finish the task. Sorry about the confusion.
Where I used to work we bought rights to a hardware database. I don't remember the name of the company, but they had any standard parts you could imagine(springs, screws, washers, bolts). They came in family tables with all the standard sizes. We paid a fee to have unlimited access to these files. With a little searching on Yahoo! the company should be easy to find. I do not have full internet access here at work or else I would help.
There is one problem though. Most companies have their standard parameters for drawing number, material etc..,. These parts may differ slightly. For example they might use MATL for the material designation and your company may use MATERIAL. If your Ilink is set up to look for a certain parameter, then you will have to go in and manually change, or add them to these models. This obviously cuts into the convenience, and cost effectivity of these parts. But if you have no such problems (or they just don't bother you) it is a very good way to go.