Cocker Spaniel Training difficulty

Question
We are having difficulty training our cocker spaniel puppy "Lucy".  We have trained our 2 other dogs but never had one that continually soiled where they slept.  We got Lucy our almost 4 month old puppy 1 1/2 weeks ago at the pet store, we knew she had been there for awhile.  Will her stay at the pet store prohibit her training or is there a better way than crate training to train the puppy?

Answer
Unfortunately, pet store dogs are often the hardest to train, and I don't advise anyone to purchase their dogs from pet shops, since they buy from "breeders" (really puppy mills, for the most part) who also keep dogs in conditions that are not usually conducive to proper socialization or house training.  In addition to the fact that you bought her at an age when she is well past the optimal socialization period, she has had plenty of time to become confirmed in the habit of soiling the den.  Therefore, the best method you can probably use to train her is to tether her to your belt.  That way, you are always there to interrupt her if she starts to go inside.  Simply say "eh-eh" (do not scold, however - some dogs will just learn to be afraid to do their biz in front of you).  Then, ask "outside?" and take her quickly out to finish.  If she does, you can praise, or offer a treat (wait till she just finishes, so she doesn't stop mid-stream or mid-poop, and don't treat every single time, but do use the words "pee" or "poop" as she finishes.  Those will become a cue later, so that you'll be able to tell her to  "go pee" and she will:-)  When you must crate her overnight, set your alarm and get up to take her out before she has a chance to soil.  Just take her out, let her go, praise quietly, and put her back in the crate with no fuss, so that she gets used to the fact that you will be going back to bed. No superfluous talking and no playing or treats.
Hope that helps, and please, next time, don't buy from a pet store.  The suppliers of those pups do nothing to insure the genetic health of the puppies they breed, you are not "rescuing", you are merely supporting a system that should be stopped.  If the worst that happens is that this dog takes a while longer to house train, you are very lucky.  Some of my clients have had pet store dogs that required thousands of dollars in vet bills to correct genetic orthopedic problems, or cure parasitic diseases or parvo, etc.  Not good.  
Anyway, good luck with this, and I hope that once you get over this hump, your dog has no more problems.  Do get her into a puppy class immediately so that she doesn't develop a fear of strange dogs and people, especially if you aren't able to have contact with lots of other dogs for her.  You can find a trainer at these sites:
www.clickerteachers.net
www.trulydogfriendly.com