Hi to upload a pic to here many use flickr to do so. Personally I use photobucket as there are no limits as to how many pics you can upload a month. but the choice is yours. If you pay Flickr and go pro there are no limits.
Here is the way I do it for a guide
Sign up to www.photobucket.com
(if you use firefox there may be some probs with this - no probs whatsoever with Internet Explorer)
Then go to bulk uploader.
It will ask you where you want to look. Find the files on your computer and click upload.
When they have been uploaded you can then go and edit them. Always necessary if you want to have a decent pic and not one that is humungous that makes the use of the scroll slidy bar necessary to view it.
When editing I always use the resize button first then click in the preset sizes and click medium.
Then I save as a copy - yes this means 2 pics of the same but in the past when I have tried to click back to a bigger size it doesn't give me the option. Eitherway its no big shakes if you dont save as a copy cos you have always got the original on your pc to upload again if needs be.
Then once you have saved, below the picture and to the right will be various options ie Share URL - Email & IM, Direct Link - Layout Pages,
HTML Code - Websites & Blogs, IMG Code - Forums & Bulletin Boards
You just highlight which one you want and it automatically copies the link and you then paste this in your posting. For this I use the Image code link and eh voila you have a piccy posted.
I hope this helps some.