Some people say that English speakers 'eat their words'. This affects the pronunciation of unstressed syllables, and is how 'want to' becomes 'wanna', and 'let me' becomes 'lemme' in informal English. Learn and listen to these examples.
Level: Intermediate to Advanced. You need RealPlayer. Go>
Three BBC radio programmes on the subject of connected speech. You can listen online or download the mp3 file by right-clicking and selecting 'Save target as...' There is also a pdf file of the script.
Level: Upper Inter to Advanced. You need Adobe Reader. Go>