How can a general consumer/user help support Ubuntu?

I think actions speak a lot more than money; openoffice.org is funded by a large company, and ubuntu is able to fund a fair few developers.

IMHO the best thing to improve for someone who is not coming from a programming background is documentation. Software developers are usually really bad at this, partially because its hard to detach ones knowledge of the interior of a system when you are trying to explain it.

Many projects have very poor documentation, and it shows; tapping away at this for an application you think is good, you use reasonably frequently, and feel is stable (so your documentation won't become irrelevant), is probably the best thing to do, in my opinion.

Whilst filing bugs is useful, its not exceedingly useful on large projects, as often the rate limiting step is fixing them, not filing them. On small projects however, it may be the reverse.

Freeing up programmers time to program could be very helpful, and you are probably a better writer than most programmers :)

I agree with mycae--documentation is always needed and extremely important. I'd also like to add that the importance of good artwork in free software should not be trivialized--contributing artwork could be very helpful as well.

For more information about the ways in which you can contribute, see http://www.ubuntu.com/community/get-involved and https://wiki.ubuntu.com/ContributeToUbuntu.

If you're interested in making financial contributions, you can donate money to Ubuntu at http://www.ubuntu.com/community/get-involved/donate. You may also be interested to know that Ubuntu is (actually quite closely) based on another Linux-based operating system called Debian. Debian is a community project, not affiliated with any for-profit corporation, and accepts donations too (http://www.debian.org/donations). The Free Software Foundation provides funds a very important software development project (the GNU Project) which produces and maintains many critical parts of Linux-based operating systems including Ubuntu; the FSF also drafts and maintains several highly popular free software licenses (such as the GPL) and does considerable free software advocacy. You can read about what they do at http://www.fsf.org/about and donate to them at https://my.fsf.org/donate/.

The GNOME project is responsible for most elements of the Ubuntu desktop interface--you can donate to that project at http://www.gnome.org/friends/. In the same way that Ubuntu includes GNOME, Kubuntu includes KDE; you can donate to the KDE project at http://www.kde.org/community/donations/. The Linux Foundation supports the development of the Linux kernel and of standards pertaining to Linux-based operating systems--you can donate to that project at http://www.linuxfoundation.org/participate/linux-donate. The Linux Fund, as you might not know from its name, raises money and contributes it to a number of different free open-source software projects (not specifically the kernel called Linux); you can donate to the Linux Fund at http://www.linuxfund.org/donate/.

You mentioned GIMP--you can donate to that project at http://www.gimp.org/donating/. As an artist, you might also use Inkscape--you can donate to that project at http://inkscape.org/donate.php?lang=en. I'm not sure how to donate to the Libre Graphics Meeting these days, but the Meeting provides a forum, as well as financial support, for work in various FOSS graphics projects; you may want to look into this. (You may also be interested in attending.) As you mentioned, you can donate to OpenOffice.org (http://contributing.openoffice.org/donate.html). In addition, OpenOffice.org is being replaced with the fork LibreOffice starting in Ubuntu 11.04 due to concerns about sustaining software freedom; you can donate to support LibreOffice development at http://www.documentfoundation.org/contribution/.

This is by no means represented as an exhaustive list of good software development projects to support, but is instead based on the information you provided. (For example, I think http://openbsd.org is an excellent project, but it may not be a project that you relate to as much as, say, Debian or GIMP.)

Upgrading your Ubuntu One account or buying from the music store will support Canonical Ltd., and Canonical is certainly a much better company to support (if you're interested in supporting free software) than a company like Adobe, Autodesk, or Microsoft. But if your goal is to support free software development, I'd suggest donating artwork, documentation, and whatever else you can provide...and, secondarily (but also very helpful), donating money directly to free software development projects themselves.

I had a look at art software you talk, but very few people ask question about them. The single exception is OpenOffice.Org, but it's the software which has currently the best support.
So I agree with Mycae, documentation could be a good way.
Another way, it you work in graphical art, should be working to improve look and feel of software. Sometimes ago, Ubuntu graphical chart was known to be ugly! Have a look at https://wiki.ubuntu.com/Artwork?action=show&redirect=ArtworkTeam

http://www.ubuntu.com/community