I would like to put 2-3 wifi based cameras in different rooms of my
house and then transmit the feed on net for me to view online
anywhere.  Also, would like the feature of controlling tilt/pan of
each camera remotely.  Finally if there is a way to transmit all or
one of the feeds to a hand-held monitor either over 2.4 or 5.8 GHz
network, that would be great too.

Any ideas on how I can build this whole solution?

Here is a free class to learn about wireless networking at cnet.com

  http://courses.help.com/courses/overview.jsp?courseId=1007

In this article:

http://www.andybrain.com/extras/sbc_yahoo_digital_lifestyle.htm

...I wrote about the Linksys WVC11B. Check it out here:

http://andybrain.com/links/55.htm

This camera should meet your requirements, though the hand-held
monitor transmission requires additional equipment. To enable that,
you'll have to get the camera broadcasting to your LAN or the
Internet, then have the hand-held monitor be able to access the LAN
itself. So there needs to be a little intelligence associated with the
monitor (like have it be a handheld PocketPC - this unit won't
broadcast to a TV or equivalent. It needs to talk to a web
browser-enabled PC.