if i already have a 4 port LAN router and want to at the very least give internet access to a wireless laptop. Can I do it without having to replace my router?

anyone? anyone?

I don’t trust anyone who’s in the position to try to sell me something i don’t need (don’t start). I started to go to CompUSA then I heard about one of those Colesium computer shows in town today, but that seemed like too easy an opportunity to get stuck with something I couldn’t return.