Hi Stephanie,
Yours is quite an unusual request, as most beaders who work with seeds use offloom weaving techniques, especially peyote, to create beadwork from photographs (example: http://cs.beadandbutton.com/bnbcs/forums/p/9556/43179.aspx#43179 ).
One of the few beaders that comes to mind who's blog could be of help to you is The Lone Beader. She does award-winning multimedia bead embroidery sculptural type work that can't be explained, it must be seen! She keeps step-by step logs on her blog, has several websites and it's worth some time to take a look at them. Her blog is here: http://blog.thelonebeader.com/, from there you can access her various other web presences.
Where to start - you need to start with a lightweight tracing paper. Tape the tracing paper at the corners to a normal sheet of white paper (so your printer won't mangle it) and make sure to place the two pieces you taped together in your printer so that the tracing paper side will get printed on, not the normal paper side. It should all lay flat so it feeds nicely into the printer. Print the image you want to use making sure its sized correctly for your project. Wait a minute before handling the printout so the ink will be perfectly dry. Remove the tape from the corners with care and discard the normal paper.
If you're using a xerox machine to transfer the image, same procedure with the normal paper and tracing paper.
You now have your image to be beaded.
Take the printed tracing paper and cut out the image leaving a good (1/2" or more) margin all around it. Now center the tracing paper on the foundation you'll be using for beading, and baste it to the foundation through the margin you left, making sure its secure.
You will actually be embroidering through the tracing paper - it does not need to be removed, and once your beadwork is complete, you won't even know there's tracing paper underneath it! Just baste it on and embroider. It will feel weird at the beginning, but trust me...it works perfectly.
Where you start embroidering is not really an issue, but if you haven't done a whole lot of embroidery I'd start from the middle and go outwards.
To transfer a cross-stitch image, a photograph, a drawing or anything at all, the technique with the tracing paper and printer or xerox machine will work perfectly. The only problem with the cross stitch pattern is that you'll no doubt lose the grids if you use a xerox machine, only the colored parts will be transferred...probably - not entirely sure about that. Another note about xerox vs. printer - if you can get a color xerox copy done anywhere, go for it - you won't have to keep referring to the original image for colors that way.
Hope that helps! :)