What capture card should I buy?
Remember that all Firewire cards are created equal. A bog standard firewire card is less than $25/£25 and combined with video capture software, will enable DV capture from your camcorder. You can get a freeware DV capture app from http://www.carr-engineering.com/dvio.htm
If the link is dead, do a search for DVIO in google. If you're not going to edit your footage, this is a very cheap option! If you do want to edit your video, you can pick up a cheap video editing suite such as Ulead Video Studio, Pinnacle Studio or Pure Motion edit studio. Reviews and guides to these can be found at http://www.marcpeters.co.uk/guides.html
Some manufacturers bundle a standard firewire card with video editing software and call it a video editing card. These usually retail for less than $100/£100. Because the cards don't offer any hardware acceleration, you'll want to make sure you get the best bundled software. Find the video editing app you want, then buy a card that comes with it!
You may also get analogue video connections to enable video transfer from VCRs etc. But if you're going down the DV route, make sure you get a firewire card bundled . Some "video editing cards" at this price range offer a USB connection.
The next "range" of cards are around the $500-700 mark and offer a sophisticated video editing suite such as Adobe Premiere, with a dedicated video editing card (harware accelerated transitions etc)