Recommendations for dual monitor setup for a PowerMac?

Hello again.

I was wondering if anyone had experience getting a dual-monitor setup 
running with a G4 PowerMac (Mirror Drive Doors model)?  It's got the ATI 
Radeon 9000 Pro card, which appears to have 1 VGA and 1 ADC output.  Is 
it simply a matter of buying the ADC -> VGA adapter (expensive and hard 
to find, apparently) and plugging in the second monitor?  Is there 
anything I need to play around with in System Preferences?

I'm currently running a very old 21" CRT monitor at 1920x1200, and like 
the 'real estate' of that resolution but text can be a bit small at 
times.  I'm looking at something like a pair of 20" LCD screens side by 
side.

Any advice, including brands to NOT look at, or even a note to let me 
know that it's just an awful idea and to just buy a new 24" LCD instead 
are much appreciated.

Cheers, and thanks in advance.
Andy.