Charts
Ukelele
circle of fifths with tabs:
(from http://thepeakoilpoet.blogspot.com.au/p/my-ukulele-page.html)
Guitar
circle of fifths interactive: http://www.all-guitar-chords.com/circle-of-fifths.php
ultimate chord chart: http://csusap.csu.edu.au/~lbenton/download/guitar/chords.pdf