There's a lot of good writing advice out there and perhaps one of the more "universal" recommendations aside from writing is to read, read, and read*. My personal pet peeve when talking to aspiring short story writers is that they don't read short stories, instead citing novels they've recently read (which isn't a bad thing, mind you, but short stories are different from novels and each one has its own set of skills you need to nurture).
Of course one excuse I might hear is that a) I don't have money or b) I don't have time. If you're reading this, it means you have access to the Internet. There's a lot of good fiction online and it's available for free. Here are some recommended sites you might want to visit:
Free Speculative Fiction Online - A database of various stories around the Internet, compiling links to them in one website. You can search by author or stories nominated for awards.
ChiZine - A quarterly horror magazine that features an ensemble of poetry, fiction, and assorted features (including columns and interviews).
Strange Horizons - A weekly speculative fiction magazine that features fiction and poetry each week.
Clarkesworld Magazine - An online speculative fiction magazine that features two fiction pieces each month (one of which gets podcasted).
Lone Star Stories - A bi-monthly speculative fiction webzine that features consistent fiction and poetry.
Fantasy Magazine - An online magazine that features new fiction every Monday (plus the occasional podcast).
Ideomancer - A quarterly downloadable magazine on speculative fiction which embraces science fiction, fantasy, horror, slipstream, and flash.
Abyss & Apex - A quarterly spec fic magazine that includes fiction and poetry.
Helix or Transcriptphase - The former is a quarterly spec fic magazine on its last issue while the latter site reprints work that was originally published in Helix.
Subterranean - A quarterly magazine with selected content available online.
Night Shade Books - An independent press which has some excerpts and fiction available for download.
Small Beer Press - An indy press publisher (go buy their books!) that has selected fiction/non-fiction from their magazine (Lady Churchill's Rosebud Wristlet) and books available for download.
Tor - A massive SF&F portal from one of the big publishers that includes various fiction and podcasts.
Now what I like about podcasts is that you can multitask while listening to them, whether it's the daily commute or performing some monotonous task such as sweeping the floor. But I'm not about to recommend you podcasted fiction but rather podcasts which focus on the craft of writing. Get motivated and learn while doing chores!
Writing Excuses - A weekly 15-minute podcast that focuses on various techniques when it comes to writing. Hosted by two novelists and a cartoonist.
I Should Be Writing -
Odyssey Podcasts - 15-minute Audio excerpts by guest lecturers from the Odyssey Writing Workshop.
The Secrets Podcast - Although it's now defunct, Michael Stackpole nonetheless gives helpful writing advice in The Secrets series of podcasts.
Adventures in Sci Fi Publishing - Features interviews with various authors although Shaun Farrel, one of the hosts, tends to ask those relevant "writerly" questions. They also recently had various interviews with the Clarion Workshop speakers and graduates.
The NanoMonkeys - Really short, daily podcasts during NaNoWriMo to get you in the groove of writing your novel. Pssst, it's almost November.
*More esoteric advice might include reading slush piles or becoming a book reviewer (the latter's my suggestion as I've doubled my reading pile and variety of books that I'm actually reading thanks to the necessity of meeting quotas) but let's stick to exposing yourself to reading more fiction first.