Yeah, the under-supported and undocumented 'proprietary' wireless drivers are a problem in Linux.
To solve the wireless issue, you can boot the live CD, then open a shell and type 'lspci'. That'll tell you what the wireless device is. Then you can use that as a search term for google.
In my case that's: 0c:00.0 Network controller: Broadcom Corporation BCM4328 802.11a/b/g/n (rev 03)
So take that model number and type it into a search engine along with 'Ubuntu', and usually you'll find a few articles that address it. Sometimes adding 'HOWTO' to a search narrows it down, but often doesn't turn up any results. If you find hundreds of articles complaining of the problem, usually someone has solved it and posted how.
http://www.google.com/search?hl=en&q=Ubuntu+BCM432
And after a certain amount of groping, comes up with an article like this...
http://ubuntuforums.org/showthread.php?t=297092
Under 7.10, it had to be a specific version of ndiswrapper that needed to be downloaded and built, and Dell's version of the Windows driver to make it work.
There were also sound problems in 7.10, and under 7.04, the bluetooth wasn't recognized, either.
When I installed the 64 bit 8.04 version, there were no sound issues and the ndiswrapper that was installed worked just fine with the Dell driver. There were some fresh new sound driver issues in the 32 bit version though. Anyways, under both versions I was able to install the 'Windows Wireless Drivers' tool, then tell it to use the .bcmwl5.inf file, and it worked immediately.
So on the plus side, it gets easier every time, but it would've been MUCH easier if I had been more selective about the PC hardware I bought in the first place. Better research into Linux hardware support compatibility ahead of time would've avoided all of the issues completely. Of course, what I actually did was buy a Windows machine, got Vista, and decided not to run Windows anymore. For a long, long time I'd been developing for Linux under virtual machines. When faced with Vista, and the breakage of ALL of the native Microsoft development tools I had paid lots of money for, Linux seemed a lot more easy and familiar.
Anyways, a virtual machine is the easiest way to 'try' Linux and even run old OS versions for support. It's really easy to keep VMs around dating back to the 90's, whereas those older OSs usually don't work well with the new native hardware. For instance, it's interesting to boot Win98 and have a live wireless connection working for it. To Win98 it looks like a wired connection.
Ubuntu 8.04 will even install into a file on a Windows partition with Wubi, and you can use Windows Add/Remove to uninstall it if it still doesn't work the way you like.