Getting there
The cheapest and easiest way is with easyJet direct from Liverpool to Basel. There's info on getting from the airport into Basel on easyJet's site. They also fly from Liverpool and East Midlands to Geneva, and from Luton to Zurich.

Places to stay
Hotel list
Official hotel guide (quite big Acrobat file)
More hotels

We stayed in the Steinengraben. It's quite central, and about half a mile from the station (map). It's about the cheapest place in Basel, but it's adequate. There's a little bit about the hotel here.

Guides, etc
Rough Guides (select on Switzerland, then Basel or Geneva)
Geneva guide (really good guide with lots of useful info)
Basel guide (ditto)
eztrip guide

City centre street map thing (link takes you to aerial photo - click on "Wechsel auf Stadtplan" for map)
Swiss Railways site

The ground is about a mile and a half from the city centre and station (map). It's a bit far to walk, so tram 14 from the city centre is a better bet. If you're staying in a hotel in Basel then you should be given ticket allowing you to travel free on the public transport.
FC Basel official site (not very friendly or useful)
Freak's Basel
European Stadium Guide

A reminder that the currency is the Swiss Franc. Basel is on the border with France and Germany, so it's possible that some places will take euros. But don't count on it!