In general…I used investopedia.com as a resource. I found it clearly written and very helpful.
I found (and your mileage may vary) that I usually got questions that tested knowing there was a penalty…or the age in which it occurred…rather than specific “do this IRA” calculation. I guess you could get a sim on it…but I didn't, and found sims were usually more general. IRAs aren't that complicated really…there are 3 MAIN kinds to worry about (I don't count the Coverdell, which isn't really an IRA)…
Traditional
Roth
Non-deductible
The things to remember are that the income phase outs exist…I don't know if you need to memorize exactly what the dollars are, but know they DO phase out and have a rough idea of how/when. Know, roughly, maximum contributions. Know the differences and how/when they're taxed (front end, back end…little of both). Know the ages that the penalties occur and what, roughly they are. I could type it all out in an hour with 10 minutes of research (I know the rough guidelines, but not specific dollar values).
It's less a big deal than it might seem if you aren't comfy with it. IRAs are pretty easy really…you'll get it…it's the defined pension calculations that are annoying. I did get a sim there…an easier one than I had prepped for. DEFINITELY know your defined pensions.