I looked on Google for Linux support for Promise controllers. They make a range of products from cheap to very expensive. I entered the following line as a search string at the Google web site.
Linux+driver+Promise+RAID
There are many hits. One of the first hits listed gives a page at the Promise web site intended to help users find the correct driver for their Promise controller. This lists the controllers for which they have drivers and it matches those to different operating systems, including two Linux distros.
http://www.promise.com/support/downl...wnload_eng.asp
You can look over the list of controllers to see if any of them meets your price/performance criteria. Then there was a page at faqs.org about installing and configuring certain Promise driver software.
http://www.faqs.org/docs/Linux-HOWTO...ID1-HOWTO.html
Here is some more information about RAID drivers in general, certain RAID controllers made by various manufacturers, and other related stuff.
http://linux.yyz.us/sata/faq-sata-raid.html
Here is a web page talking about RAID on Linux. It specifically talks about using the software RAID capability of the device mapper module in the 2.6 kernel to drive SATA hard drives in a software RAID configuration.
http://linuxmafia.com/faq/Hardware/sata.html
Now you asked about an Adaptec product. Maybe you prefer their brand. So I did another search on the Google web site using this search string.
Linux+driver+Adaptec+RAID
Here are some page hits regarding this subject.
http://www.adaptec.com/worldwide/sup...uct/AAR-2020SA
http://www.adaptec-de.com/worldwide/...2FSuSE+Linux+9
http://people.redhat.com/tcallawa/dpt/
The web page listed above for the linuxmafia web site also mentions Adaptec products.
Google is your friend. Enough said.