Which upgrade should be my priority?

thanks guys,anyone own atacama stuff or can recommend any other good speaker stands?

Personnaly I give natalie my vote.The other tweaks are a waste of money if the signal isn't there to begin with. You are obviously looking at the right web-site to do just that.
Find a good pre-amp and amp and build from there then any tweaks will bear fruition.

If budget is tight, you could use cloth-covered cinder(sp?) blocks, so you can save for an amp. I used to have a pair of stands that were work well, sand-fillable for ~$80. I think the brand is Premier. They are often sold with Paradigm monitors. Call Hillcrest Hi-Fi in Dallas, they'll know what it is for sure.

You might consider a dedicated circuit from your service panel with hospital grade outlet. All of the other upgrades will be much more effective with this upgrade. Cost should not be more than $150.00 if you hire an electrician, less if you can do it yourself.

Good Listening

I'm with the others. Lets reedit.

1) Speaker stands ($50-whatever)
(wood can be nice if done well, if you do metal it must sand filleable. I've used the Cinder blocks myself, I feel like a tweek saying this, but turn them so the holes are facing you--should minimize diffraction more)
2) Acoustic Treatment (<$75)
3) Cables (DIY)
4) Deadening speaker cabinets w/ dynamat (<$50)

These'll get you mileage until you get your better components. Decide which ones you can use in your system since you didn't specify your speakers or other things. Look up the older threads like, "best cheap tweek" "best inexpensive tweek" etc.