When I opted to try self-publishing a script I chose Lulu Press. I don't regret the decision. From their publishing guidelines, I learnt that the whole process depended on how you prepared your manuscript-getting the basics right. Truely, the rest of the processed went through, smoothly, for me!
Whenever I queries they were answered and follow ups done as well. I found Lulu Press to be a friendly press, even the quality of the printed copies was super!