Are all stimulants for adhd addicting? or do they have ones that aren't as potent but still are as effective? such as extended release?

Yes.: All stimulants will change your body/brain to need them. Low potency stimulant/high potency/delayed release. Same. If you need them to function then use as doctor prescribes.

Not likely to addict: The most common and probably among the best medications for ADHD are stimulants. Studies have shown that when taken as part of a formal educational plan, addiction is not a significant concern. However, when taken as self medication or when combined with other abusable medications addiction is a concern. Alternatives include Provigil and Nuvigil which are less potentially addictive.