The site claims uniforms of the 30yw but shows only plates of Spanish, but it is worth it just for those
http://www.balagan.org.uk/war/thirty-years-war/painting-guide.htm
Cheers, Rob :)
Here's some more uniform info on the parties involved:
1. George Gush (http://greatestbattles.iblogger.org/Renaissance/RenaissanceWarfare-AirfixMagazineArticles.htm)
2. Pierre Picouet (http://usuarios.multimania.es/ao1617/tercios.html)
3. More Picouet (http://ao1617.0catch.com/europe/contenu.html)
4. Alabarda (http://www.alabarda.net/uniformes/esp/inf/tercios/tercios.htm)
5. Early Modern Warfare Society (http://www.xenophongroup.com/EMW/EMW.htm)
6. Tercios de Flandes (http://ejercitodeflandes.blogspot.com)
7. La época de los tercios (http://www.tercios.org)
And the best primary source of all for things TYW-ish:
8. Theatrum Europeanum, oder Warhaffte Beschreibung aller … denckwürdigen Geschichten, so sich hin und wieder von 1629 biß 1633 zugetragen. (http://www.bibliothek.uni-augsburg.de/dda/urn/urn_uba000200-uba000399/uba000236-uba000256)
Cheers,
Aart