Espresso (as you've seen already) isn't easy and reveals every apparent flaw in technique, equipment, etc. Grind a few grams of beans in your Krups and hold in your hand and look carefully at the different particle shapes/sizes. For great espresso you want those particles to be quite uniform so the water can flow through them evenly. With cheaper grinders you usually end up with boulders and dust, leading to very uneven extraction.
Most coffees roasted for espresso will benefit from resting at least 3 days from actual roasting. There are many good online roasters, but something local would be better if you can find a few. Just don't pick up something off the shelf of a local Starbucks, etc. and expect great results. Any coffee (provided it was grown, processed, roasted with care) can be great as long as it's fresh, just some work better for espresso, etc. than others.
A simply digital gram scale will work great. Not saying it's totally necessary, but will help with consistency and minimize waste. There are other ways to determine the best dose for your machine/coffee, but using a scale will minimize alot of aggravation along the way.
Again, I'd let it warm up 30 mins... When the light shows it's ready that early simply means the water in the boiler is ready, highly doubt all the metal is. Run hot espresso through a cool-warm portafilter/basket/group and you have a weak/thin/pale shot.
Also, get a decent tamper as that will make the process a bit easier. Not necessary to spend a ton on one either.