I have just joined an Aussie swap on ravelry that involves making a project bag. I promised that I would dig up some suitable tutorials and links.
U-handbag (UK) is a great resource for making bags and it has a great post on bagmaking for newbies.
Nicole Mallalieu is an Australian designer that focuses on hand made bags. Her site has lots of great patterns and supplies and her blog is full of tips, techniques and tutorials. Another good Aussie selling hand bag supplies is tall poppy craft.
Here are 5 of my favourite free patterns that I think would be suitable.
From all people quilt the grab bag pattern (pdf file)
I have made a few of these and they fit a one skein or sock project very comfortably.
Martha Stewart has a tote bag using bias binding to hold it all together.
This is the one I made from that pattern. It is good because it can easily fit a magazine or pattern sheets in the side pockets. It is a little tricky to get a hang of using the bias binding though.
This pyramid purse is a free pattern at Living Creatively. It is quite small but I think it could be sized up to make a decent sock project bag. This is very similar to the ever popular sunny-boy project bag.
This could easily be made to any size and it has great step by step photos. The steps to make this bag are fairly simple and is an excellent starting point to make any type of tote – eg add pockets or shorten the handle, or make two handles.
And if you want a tutorial to make absolutely anything go to oneprettything.com. She has a list of tutorials of things to make for crafters and it includes pin cushions, needle rolls, sewing machine covers, post office bags (great for an etsy seller), covered tape measures and cloth labels. Well worth a look.
I hope this helps.