This is a nice little book. It contains all of Lovecraft's more obscure short fiction, most of the stories are 'collaborations' with other authors, which usually means that someone else would submit an idea to HP and he would pen it for them. The only collaboration omitted from this collection is The Loved Dead, which seems to have been removed for legal reasons.
I could only recommend this to Lovecraft fans, it's not the best of his work and would be a terrible introduction to his writings. If you're curious about Lovecraft, buy the Penguin Classics 'Call Of Cthulhu and other weird stories' for a great introduction to his work, it's volume 1 of a 3 part series which collects all his major works. If you have those 3 combined with this book and 'The Loved Dead', then you have his complete works of fiction.