Did you say you are interested in some data wrangling? Or perhaps some data scraping? Wait, you say you just want to learn how to clean data and maybe geocode it? For all this and much more, log on to School of Data now! You can even take a course online. The following are some of the recommended tools:

Extracting: Google chrome scraper extension, Google spreadsheets, Scraperwiki, gImageReader + Tesseract

Cleaning: Open Refine, Spreadsheets, Nomenklatura

Analysing: Spreadsheets, R, Gephi

Presenting: Tile Mill, Fusion Tables, Gephi, Many Eyes, D3

Sharing: The Datahub, Google Docs, Github

Source: School of Data

PS: Other good places to check out are Codeacademy and the resource page at Exposing the Invisible.