Ive come accross a pretty good site for Welders et al.
Ive emailed the webmaster and they seem to have some bigger plans in the works, as in downloadable java apps for pipe and sheetmetal. You will apparently be able to do this from certian cell phones.
Anyhow they have some content in the way of articles, some basic plans and pipe templates for Branch and Trunk, etc etc.. Oh yeah, they are still working on dis-similar pipe templates.
James