A guide to geostatistical mapping with open-source tools
Mapping with R and other free and open-source programs feels clunky and hacked-together at times. The plus-side is that it's all for free, and once you find the time to wrap your head around it, you can get quite a bit done. Tomislav Hengl provides a free e-book, A Practical Guide to Geostatistical Mapping, that can hopefully help you with such tools (namely R, SAGA GIS, and Google Earth). You can also buy the paperback version on Lulu.