Could you be using too harsh products so that your skin reacts by producing more oil?
I used to have really oily skin and I used too harsh products which made it worse. I have also had hormonal/adult acne, and I found that the Clinique Anti-Blemish range was good - the toner is harsh, so I'd give that a miss, but the moisturiser was very good for me.
I'd suggest to use a really mild cleanser - I have oily skin and I really like Cetaphil.
An oil free moisturiser that is not too harsh would probably also be good. I like ROC Hydra+, but there are many others on the market.
I have oily skin, and I use:
Cetaphil
ROC Hydra+ (or some kind of serum as I find them to work better than most moisturisers on my skin - layering serum and moisturiser is too much generally for me)
A mattifying primer is nice IMO, either alone or under makeup. But I don't always use it and don't always need it.
At night, I use a cleansing balm to remove makeup and dirt (I like Clinique Take the Day off Cleansing balm and the Body Shop Camomile Cleansing butter - they are very similar; they get all of the makeup off and do not leave a film on the skin).
Then every other night I use Alpha H Liquid Gold - this has made a massive difference for my skin, both regards to texture, spots, scars from spots and oiliness. However, it is harsh on the skin (and not cheap - I buy it when I see it on offer), so maybe you would want to try something milder (Pixi Glow Tonic is also nice) or wait until you have tried if another cleanser and moisturiser make a difference for you.
I don't find that oily skin and foundation is a bad combination - but it can be hard finding a good foundation for oily skin. I don't like full coverage and too matte foundations, and that seems to be what is generally made for oily skin.
I am currently using Clinique Anti-blemish solutions BB cream with SPF40. It's very liquid and I use 3 drops for my whole face, but I really like how it looks and how it wears. It apparently contains some of the same ingredients as the moisturiser from the same range and it is supposed to help to not break out.
No matter what you end up buying, I suggest that you ask for samples (especially if the products are a bit more expensive) as it's so annoying spending a small fortune on something that doesn't work well.
Also, some people tend to say that you need to allow for a purge period when starting with new products - a period of time where your skin gets worse before it gets better. This is a myth. If a product breaks you out, it's not right for you.