IMO, one of the greatest cards ever printed. A shame we gotta see it go eventually =/ We have cards sporting similar effects like Alph Lithograph 4, but Azelf is easily searched for and not only lets you look at your prizes but ALSO get a Pokemon there. Currently, its utility is unmatched.
On paper I would give this card a 10/10, but if you've played with it you can see a couple flaws. For starters, its Power can be Sprayed. Obviously everything with a Power falls under this category, but its something to work against nonetheless. Also, it's a pretty terrible start since there's no way to get it back into the deck like Uxie's Psychic Restore.
That's not to say Lock Up is a bad attack, it actually has great utility. I would have preferred seeing it being colorless, but it's a small gripe. In a format with so many Trainer locks (on both sides of the field), Lock Up can probably buy you a turn or even set up a KO. Your opponent basically needs to rip into a Warp Energy under Trainer lock, and even then you make them dedicate an attachment to get out of Lock Up.
More on the plus side, 70 HP is solid making it a safe start and putting it just out of range of Shadow Room (without the aid of Crobats). 1 retreat is great. Azelf even has a Level Up with decent utility, a decent card in Psychic based decks to get rid of weaknesses and it also has a decent attack. I'd have to say Azelf brought a lot to the game, allowing more decks to run single or 1-1 techs without fear of being prized. It introduced a new level of consistency that prize issues had a hold of.
9.5/10