Hey there ... best two places to get a freebord would either be direct from the makers themselves in the states
www.freebord.com or the uk dist
http://www.ukfreebord.com/
On freebord.com complete boards range from about £100 up to about £170 for a package that includes upgraded wheels / bearings and other extras. You'll have to add postage and packaging onto this of course and that'll be about £35.
I'd recommend getting the basic package with either s1 or s2 bindings to start with as you can always upgrade your wheels later. I started out with the basic package with s2's (these are a little more like snowboard bindings and hold your feet in a little better) which works out at £137 including postage and packaging. Might take a week or two to ship from the states though, and you may or may not get hit with import tax ... I didn't get hit with that when I bought mine.
Other option is to buy from the UK dist
http://www.ukfreebord.com/ where a basic package with s2's will cost you £165, you'll get the board quicker if it's in stock.
Seems the exchange rate just now is working in our favour, so long as you don't get hit with import duty.
Short of that, try the ever popular ebay

I know a few guys on this forum bought theirs from ebay .. you could even try some of the people on the forum and see if they would be willing to sell theirs. There are a few people with freebords who aren't out riding them too often.
As for how close it is to snowboarding, it's pretty damm close. I was looking for something to keep in with my snowboarding during summer and I think it's great for that. It simulates the sliding aspect of snowboarding pretty much perfectly ... carving less so. You should get the hang of it reasonably quickly if you've been snowboarding a lot. It's just getting used to the idea you're not on a skateboard ... you are always riding an edge on the freebord just the same as on a snowboard. The way board "rocks" because of the center wheels is a little disconterting at first but once you are used to it you'll be spinning and sliding in and out of switch no problem. Be prepared to take a few nasty hits though, the first few times you catch an edge on concrete is painful to say the least
Hope that helps, if you've got anymore questions ask away ... if you fancy having a go on mine I'm usually down in Kelvingrove park for the thurs night meets ... I'm the ginger bloke
Also the freebord forum is a great place for asking any questions or getting info ...
www.freebord.com/forum
I'd recommend having a look at the videos that have just been submitted for the rider contest this year:
http://www.freebord.com/forum/showthread.php?t=12753
That'll give you an idea of where the sport is and how much the ride is like a snowboard.