Welcome to CoffeeSnobs mate.... [smiley=thumbsup.gif]
Try setting the grinder so that the output feels like fine table salt when rubbed between the fingers and then give that a go. You need to ensure your dose and tamp technique is spot-on too mate and that only comes with practice, lots of threads about this can be found using the search tool.
What sort of Tamper do you have by the way? If one of those nasty plastic things that comes with most machines, youd be doing yourself a BIG favour by going for a quality, fitted Tamper from one of our sponsors... Will save you a lot of pain and frustration in the end. Best way to get your tamp force technique ironed out, is to plonk a set of bathroom scales on a benchtop and find a way that works for you, to apply a consistent tamp force +/- 1.0Kg between say 7.5Kg and 15Kg. The actual number isnt important but consistency is. The nominal tamp force you will see recommended by all and sundry is 30lb (13.6Kg) but as with a lot of things to do with espresso, this is more of a recommendation that a must do.
At first, leave the Single Basket in the box and concentrate on just the Double. The extra depth of coffee in the Double makes it a bit more forgiving with respect to Dose and Tamp. It also makes for a much more tasty and richer brew too 8-). If possible, see if there are any reputable coffee specialists running Home Barista Courses near where you live. Completing one of these will make everything fall into place for you much more quickly and give you a better appreciation of the whole process. Anyway, all the best with your new toys and many happy brews... :)