Yeah Jimson weed grows all over da place, i have some in my back yard growin wild but i dont use da stuff nemore. (I only used it a few times when i did use it.) Its really dangerous in higher doses. (It and other related plants were often used as poison and in witches brews in the past.) Its nothing like shrooms, its more of a depressant and deliriant with the added effect of some bizzar and realistic hallucinations. Most people dont like it.
The safest and prolly best way to use it is to just smoke some dry leaf or flower, or eat just a few seeds. (you could also make a tea from da flowers) then smoke some weed. They really go well together. Its better to stay below the hallucinogenic doses in my opinion, cus the trip isn't much fun and it can be dangerous in hallucinogenic doses. But i can't stress enough how well small doses go with cannabis.

If you take too much, you could get liver damage. Be very careful with the dose if you're gonna take it. In fact... Just dont take it =P, its really too dangerous for anyone to recommend.