Yes, Excel can use include .DBF (database file) and .CSV (comma-separated values). Most database packages can export to these formats.
use the VLOOKUP function, you can type the VLOOKUP function by hand, but it is much easier to generate it using the 'Paste Function' option. This can be activated by either using the menu option: Insert -> Function, or by clicking on the Paste Function Icon on the toolbar.
Either way, you will be presented with a list of Excel functions to select from. The VLOOKUP function is under the 'Lookup and Reference' category.
Hope this helps,