The following are annotated corpora and the annotation guidelines for efforts annotating dialogs. This is just a sample. For some of these corpora there are multiple annotation efforts.
ICSI Meeting Recorder corpus
Dialog Act Guidelines
Paper on ICSI Meeting Recorder Dialog Act (MRDA) Corpus
Project Site
AMI Meeting Corpus
Topic Segmentation Guidelines
AMI Meeting Corpus Overview
Other AMI Annotation Guidelines
Settlers of Catan
STAC Annotation Guidelines
Discourse Structure and Dialogue Acts in Multiparty Dialogue
ARRAU: Anaphora and Deictic reference in dialogs
ARRAU Annotation Guidelines (for TRAINS)
Anaphoric Annotation in the ARRAU Corpus