Do you mean a cell modem USB adapter or a WiFi adapter? When you said "wireless internet" do you mean it's wireless inside your house, or wireless as in a cell phone type of service.
For a cell modem, the 2 I know of are VZaccess from Verizon and Sprint Connection Manager for ahh.. Sprint.
With this and any other looking for driver issue, search engines are your friend. Just type in your USB adapter model number with the word drivers after it, and pick a link.