Check some of these sites and find material about others.
1.
Authentic communication: Whyzit importan' ta teach reduced forms?
2.
Phonology: features of connected speech
3.
Aspects of Connected Speech Index
4. Urban dictionary, a great place for reductions if you know what to search for.
5. Google for misspelled words. When you hear sko, skoda, just search for them. Surprisingly, they are reductions for "lets go; lets go to the store". If you are from counties where spelling and grammar is of paramount importance, get out of that mode, since that knowledge perverts and/or impairs your perception. Now you know why you see many native speakers misspell words. It is not because they are dumber than those Indians and Chinese, who scored 100 percentile on their TOEFL and GRE verbal, but because their speech drives how they spell when they don't have sufficient knowledge of English spelling system. That's another reason you see Indian kids on spelling bees contests, since parents of these kids are so bent on spelling, grammar. Phonetic and voice oriented parents can drive their kids to more lucrative areas where these kids can master various accents based on how foreigners syllabize and map sounds.
6. Sound patterns of spoken English by Linda Shockey
7. Simplification of constant clusters across word boundaries. In some sense, this is the major part of connected speech.
8. Resyllabification, a phenomenon linguists call, deals with syllabification across word boundaries.
9.
http://blaoism.blogspot.com/2012/01/some-reduced-forms.html
10. If you are aiming for AmE, it is a time to figure out your articulations of alveolars, r and l, since many clusters involve these constants. A bunched r with laminal t/d is a long way to master American Accent.
