Your colouring and skin sound like mine. I'm 37, with dark hair, blue eyes and oily skin ( but getting dry and wrinkly too in places ).
I've only been wearing make up for the past two or three years, gradually adding more as I get more confident with it.
I'll try and stick with budget recommendations if you're skint :)
A primer makes the world of difference, especially if you have oily skin. Can't really recommend a budget one I'm afraid. I love MAC spf 50 prep and prime. It keeps the shine at bay and my make up on my face all day.
Foundations, there's a lot of decent high street ones. For oily skin the revlon colourstay is good, or the Rimmel 25 hour one. My favourite is the Bourjois foundations though. Healthy Mix or 10 sleep effect for a lighter finish.
Blusher makes a huge difference. For your colouring, I recommend Benefit Dandelion or budget version Natural Collection Pink Cloud. Superdrug MUA do a nice pale pink one for a pound too.
I wear Bourjois mascara, and I like high street lipsticks. I like No.17 in Beehive, which is natural, or the Collection 2000 cream puff lip creams. Natural Collection do some lovely lipsticks. I have a nice every day one called rose bud or something like that.
I also fill in my eyebrows and line the outer third of my lower lash line with any old brown eyeshadow and a flat angled brush. Natural Collection do one called truffle I think. Or I have a nice GOSH eyebrow kit from Superdrug which is brilliant and does the same job.
All takes five minutes, makes me look ten times better.