Okay, so let's say I've got a nice, well protected, relatively authoritative, covered all my bases to the best of my ability, little network of sites that I'd like to use to link to my money sites. All the sites in my network are in English and hosted in the US or UK. My question: will this network be just as potent for ranking a site in foreign language, google.es to be specific. Or will a bunch of links from English sites to a Spanish one look fishy? Thanks!
It's a perfectly natural thing to do. As long as your links follow the "QUALITY > quantity" rule you will be fine and it won't look fishy.