I can actually answer this having recently (about 3-4 months ago) gotten AE, It's not free, It depends on what sort of effects you really want, for example, to make a... um... Flare go across the screen, it only takes about 4-5 minutes. Sparkles and stuff like that i'm guessing take longer. I haven't got this trapcode particular plugin. To learn, well to learn the VERY VERY VERY basics, it should take you about 2 hours. That's only figuring out the UI. Cool effects like that should take lot longer. Also, I'm 90% sure that those effects can be done in Photoshop, Infact I believe there was a guide put up recently as to making shine effects. Scroll through the guides a bit you might find it. From there it's a question of experimentation with it.