Q: extending the range of my wireless network

Thank you for your prompt reply. To clarify: we are trying to set up an airport express to extend the range of the home wireless network.  We have a DSL wireless router. do we need to purchase another airport product or can we use the Mac as a compatible base station which can be extended?

Thanks for help, I did read the links but would like to use the airport express as booster (the DSL router has multiple Ethernet connections are very handy) rather than as suggested on the link, so will try reposting the query on airport as you suggest. Paul