Audible and Visual Alerts on Windows 7

This may be a basic question for this venue, but my department depends upon IM and is accustomed to using Spark on XP where audible and visual alerts easily notify each user of a new message. Our IT department has recently migrated our workstations to Windows 7 and many pertinent IMs are not being responded to since users don’t even realize the arrival of new IMs in the background. What suggestions are there for making this more apparent in this new OS? I need flashing lights!

Thanks!