A full BOM has been posted to github.
The PDF's show the assembly details.
The "edrw" files can be viewed with a free viewer available here
The towers use 19mm(3/4") or 20mm square tube 670mm long. 180 grit polished stainless tube is recommended. Choose the 19 or 20mm version of parts as appropriate.
Each tower needs 10 pieces of 623ZZ Deep groove ball bearings. There are 8 pieces in each carriage and 2 for each idler pulley so 30 pieces in total.
The arms use carbon fibre tube with 6mm OD. The tube I used had 5mm ID and was pulltruded tube. Use some 2 part epoxy to glue them together. All 6 arms need to be the same length (250mm) as close as possible so make a jig and "set" the length as you glue them. The carbon tube length is 206mm
Nothing in the design should be difficult to obtain locally. If you get stuck http://www.makershop.co.nz is my website and we will ship internationally. All the parts except fasteners and printed parts are listed there but no kitset options - yet.
Update 11 March 2013
Added STLs for use with 20mm tube. Some countries 20mm is easier to get than 3/4 inch (19mm).
Update 15 March 2013
The Delta-Pi successfully printed its first parts. After ironing out a construction defect in the hot-end we printed an Octocat. Print quality wasn't too bad. I need to add a cooling fan and there were a few cobwebs to clean off but it was a success.
Update 5 April 2013
Added revised top and bottom boards and hot end mounting parts.
Update 3 November 2013
Added a new hub design including a touch probe for automated bed levelling.
Update 7 March 2014
Added Repetier firmware config.h file for ver 0.91