Manufacturers:  
Sylva The Mojo and Riot
RAW Engineering   The (formerly Sylva) Striker; Toyota 4AGE engine experts
Stylus Sportscars The (formerly Sylva) Stylus
Fisher Sportscars The (formerly Sylva) Fury
Stuart Taylor The (formerly Sylva) Phoenix
Useful Sylva Resources:  
Sylva Sportscar Register   Join up!  
Sylva Chat Smartgroups chat list with occasionally working search facility...
r1ot.com forums Courtesy of Richard Burgess
Useful Non-Sylva Resources:  
Westfield Sports Car Club Useful forums for non kit-specific queries, plus 'For Sale' section
Lotus 7 Club Forums Caterham forums with some info on Zetec engines and Weber carbs, plus 'For Sale' section.  Unfortunately only members can post to this forum, but it is still useful.
locostbuilders Lots of useful info, from a very resourceful group of builders!
Engines:  
zetecinside Useful source of Zetec-E & gearbox info  
fms-ford-spares Ford spares at reasonable prices  
Fensport Toyota engines and other parts  
Mojo 2 Build Pages:  
Steve Knee's build A good selection of photos
Andy Sayle's build A useful build diary of the first part of a Mojo build, currently curtailed due to a lack of webspace...
GoMojoGo Currently seems to be down...
Other Kit Car Build Pages:
Tim Hoverd's builds Including a Westfield, Dax & racing Fury
r1ot.com Riot SE build diary & forum courtesy of Richard Burgess
r1ot-act.co.uk R1 powered R1ot build diary, from Martin Boakes
shorttrack Interesting Riot build using a Triumph 3 cylinder engine and various custom components, from Jason Shortland
Mistrale An interesting homebuilt mid-engined 2 seater with a 1.25 Ford Zetec SE.