In development everything may run in a single Tomcat container or through the Apache web server. External resources can be deployed into the Tomcat thus the Internet connection is not needed for the most of development (with the exception for Google Map and related services).
Some of the JAR files need to be installed into local Maven repository manually.
Those are available in the GIT repository, both source and binary:
You can either install your own Solr or use the WAR package attached to the GIT repository download section for Tomcat development environment. It has hardcoded path in its web.xml which points to Solr home directory which needs to be changed. Note that Solr 3.5 is deployed inside of a Tomcat but Solr 5 is a standalone server.
Attached to the GIT repository download section for Tomcat development environment.
This is optional web server which delegates requests to Tomcat via AJP. The idea is to run Tomcat container as it would run in production environment and on port 80 without superuser privileges.
WAR package and database
Those components are precific to a pack as each pack has its own database schema and resources.
Please read the following articles: