You can of course use spotlight (bit clumsy) or I've started using 'Launchbar' very neat little shareware app that Apple should have included in Leopard instead of spaces. In fact I think Launchbar's interface is better than QuickContact.

Launching Now Contact and Now Up-To-Date are not a problem for me. What I miss is the pulldown menu to show my appointments and to-dos for the day and the automatic reminders (the QD daemon doesn't run under Leopard either so I get no notification about events).
Dave Sawyer
iMac 24 2.8GHz Mac OS X 10.6.2
PowerMac G5 2GHz DP Mac OS X 10.5.8
Windows XP, Vista and Windows 7