i need to let users know a simple way how an item from a list can be deleted. Is the best way to put a delete icon next to each item? It looks a little cluttered...
Show a trash can icon, but only reveal on hover
Use the icons you have, but place them in the more conventional location to the right of the text, and only reveal on hover.
Users trying to interact with the items will mouseover and see the obvious delete/remove icon.
Ensure the target area is the entire row and not just the area around the icon.
If relevant, bear in mind the ramifications for mobile/touch users i.e. click-to-hover effects in CSS, and possible increased target areas for smaller screen sizes.
Have you considered the option of checkboxes?
I am not sure how long these lists can get in your app. But perhaps, instead of forcing the user to delete items one by one how about offering checkboxes next to each item.
Then a delete option somewhere nearby and the user can delete a single or multiple items at a time.
The checkboxes will also come in handy if in the future you decide to add extra actions such as "Edit", "Copy", "Share" etc. and they are not as intrusive/attention grabbing as a trashcan icon.
Here is an example that shows what I'm suggesting (taken from http://www.androiduipatterns.com/).
Of course you can choose where you want the actions "Delete" etc to be placed. They don't necessarily need to be fixed at the bottom.
Lastly, another option would be to just add an "X" icon at the end of each entry. Even if a user doesn't know that "X" means delete (unlikely) they still get the confirmation window that teaches them and allows them to retract back from.