Not true (at 99%)!
I know plenty of laptops with cpu's not soldered in (1 of my laptops I know has an non soldered cpu. (Lenovo 3000 n200))
Now yes there are laptops with cpu soldered in but not at 99%. I would guess more around 65% to 85% [:grahamlv:3]
Although all this does bring up 1 point, you need to make sure that the cpu is not soldered in order to be taken out.
Now as for motherboard that can take a mobile cpu, thats another story. there not a lot of these types of motherboards out there.
For you all i could find out there is this motherboard.
http://www.amazon.com/IEI-KINO-690S1-Mini-ITX-Motherboard-Socket/dp/B0031YCYWE
http://wwwd.amd.com/catalog/salescat.nsf/doclookupweb/5B08DE8F63A45F3F862572BC001ED692?OpenDocument&id=IEI+Technology+Corp.~KINO-690S1
Not exactly what i would call well known and i cant find the product page on the maker website....... So there still a risk of the cpu not working even if it can go into the socket.
Now in my personal option, i think you should go build a new desktop or buy a new laptop to replace the current laptop as thats a really old cpu.
There currently cheap $40 range single core AMD Sempron cpu's that would perform just as (if not faster than) than the cpu you got. (now there is a nice little bonus for these as they got the "possibility" to unlock to a dual core cpu turning it into an Athlon II x2 (although it may not work hence why i said possibility.) All this means is that there a chance of having even more performance than what you paid for. )
So if your looking into a very cheap computer build, you can revolve around that with something thats news can at least has a better up-grade path down the line (sempron $40, AM3+ motherboard $65, 2GB ddr3 is about $20 for those 3 components will only be around $125)
Overall, as said, it's old enough that it's not really worth looking into salvaging the cpu. A hard drive, maybe but not a cpu.