Challenge: Verizon Broadband and Aiport Express; can they play together?

Question

My only access to the internet is through VZ broadband which currently uses my phone as a modem (not elegant, but it works).
My goal is to print wirelessly from my mac (all printers are currently connected to PC), stream music from my mac to the stereo and have internet throughout the house without having to drag my phone/modem everywhere.
I thought Airport Express was the perfect solution, but since I don't have a DSL/cable modem, there's nothing for me to plug my ethernet into.
What's the simplest way to get there from here?

Answer 1

The answer to your first question is "yes." You'll simply run a cable from the Express' minijack to your stereo's inputs and then use OSX 10.5's Admin Utility to set up the Extreme N and Express as a WDS, with the Extreme serving as the main base station and the Express serving as a remote station. (You could reverse these roles, but you indicate you want to retain the Extreme as your main base station, possibly because its nearest your Ethernet cable.) A possible added benefit may be improved signal strength throughout your home -- any 802.11-equipped computers you have will be able to connect to whichever station provides the better signal.
From what I've read elsewhere in this forum, it will be best to ensure the Express is also the newest, N version to preserve the added range/bandwidth of the 802.11n spec and maximize reliability. You'll want to use the Extreme's "extend network" option when creating the WDS and choose between communicating at 2.4 vs. 5 GHz. Prior discussions have indicated that 2.4 GHz yields better range and 5 GHz yields better bandwidth, but there's no substitute for trying both and choosing what works best for you.
I've no experience with iPhones, so I'll leave it to someone else to answer your second question.