Spinning problems

I've been skating on and off for about three years. Took a year of lessons then the next summer I skated regularly but didn't have resources for lessons, last year I was only able to skate a few times. This year I'm back practicing four hourse a week with an additional hour lesson. This is great but I have the feeling of really needing to 'catch-up' now so I'm taking on thing at a time trying to even out and get my basics down solid.
My big weakness is spinning. So far I've just been working on the basic one foot upright spin so if you could give me any pointers they would be much appreciated. Here's what is happening:
1) I am not centered, once in a while I will get it decently centered but it is always more by chance than really knowing how to improve it myself.
2) I have gotten into the bad habit of getting onto my toe-pick. The best I can manage is spinning with only the botton groove cutting the ice but usually I can't keep off it at all.

I think once I sort those problems I will be able to take it from there pretty well but these two things are really hanging me up.
Thank you!

Welcome to the club!
Spinning is an extremly infuriating and frustrating thing to learn, I've been literally doing battle with the scratch spin for 3 months myself.
Among the advice I've gotten for staying centered are:
Go back to 2-foot spins and practice those until you're very centered (or purple with green polka dots, whichever comes first....)
Imagine a plumb line going throuh your body from the top of your head to the spinning blades' sweet spot, and stay over or on that line.
Practice the tightening 3-turn that 'hooks' you into the spin over and over and over and over..........
Keep your arms out, do not pull them in (this actually throws me off).

What has helped me the most is keeping my spinning leg well bent while concentrating on the muscle power in that leg. Think steel rod. Even the slightest noodling in that leg and your spin is toast.
Good luck!