For each project determine the priorities of each compared to the others and set realistic expectations of when the projects can be completed and if any are time fixed (completion date can’t be moved). Split the projects into smaller phases to allow better visibility of progress to the project sponsor(s).
In terms of time tracking, something simple like http://www.keeptempo.com/ or http://slimtimer.com/ to allow analysis of the time being spent, and for more advanced projects recording against key tasks to determine if the project is at risk of going behind schedule.
Use something like ACT! or Salesforce to keep track of your relationships and activities associated with those, see the PDF at http://itredux.com/2008/03/29/extreme-productivity-seminar-slides/
Also, ‘Multi-Project Resource Leveling Can Be a Juggling Act’ from the PMI at http://www.pmi.org/eNews/Post/2008_04-25/Multi-ProjectResourceLevelingCanBeAJugglingAct.html