Self-Publishing Question

I recently had a friend contact me for advice on how to go about self-publishing her rhyming picture book about life on the farm. A former student is illustrating it for her and is, reportedly, doing a fabulous job. I've not pursued the self-publishing route before and wasn't sure what to tell her. She really wants to retain rights to the manuscript which is why she does not want to pursue a traditional publishing house. Does anyone have any advice I can pass her or idea of a good source of information on self-publishing? I'd be grateful as would she. Thanks, in advance, for any info you can provide.