The Foundation Center offers free webinars that are short online grant writing training.  Register to participate without cost.

Topics include grantwriting basics, proposal budgeting, and finding funders (as well as other topics).

The Center also offers free longer tutorials, interactive online training courses that reinforce lessons with interactivity, assignments, and self-tests.  (Some tutorials have a cost but many are free.)

http://foundationcenter.org/getstarted/training/webinars/guide_webinar.html