cable and interconnect advice?

Don't listen to people or reviews TOO much.  Get your hands on a nicer cable, maybe from a seller that is willing to let you have an in-home demo period.  Play some music you are familiar with a couple of times with your current cables and setup, then play those selection(s) at the same volume, in the same listening session with the new cable you are trying and listen to the changes.  Listen for the soundstage size, transparency, detail, speed during fast successions of notes.  Listen to the separation of notes, say the low bass guitar and the kick/bass drum.  Listen to the percussiveness of everything really...one will sound soft and boring, the other will be punchy.  One will be more smeared, there will be more blare, more harshness, more fatigue, and the other won't.  One will sound more "real" to you.  
And...if you don't hear a difference, that particular cable isn't worth purchasing.  Those who state that you shouldn't spend anything on cables are flat wrong.  Sorry.  I wish it wasn't true, but it is.  Cables are part of the system's sound.

Tritonmark...oh so wrong. Cables make a world of difference. There was talk here of Purist....very lush, great mids but to THESE EARS highly colored...they very well may be great in YOUR system. Cardas in MY system was awful...although recommended by the manufacturer of all my electronics...grainy, stuffy, etc. ...and so it goes. In MY experience, power cords make the most difference, however, I just got new speaker cables which I thought made the least difference, and it really opened up my system...never sounded so good. It may be compatibility, it may be trolls...

Tritonmark -
I used to be a cable-denier. Wire is wire, or so I thought. Don’t listen to me or anyone else as Herndonb has said. Listen to what your ears tell you. Talk to the people at the Cable Co. in New Hope, Pa. They claim to have a "database" that will help them match wire to your specific gear. Borrow some wire (ICs, Speaker Cable, Power Cords etc.) from them. Get what you can afford. Buy it if you like it. Return what doesn’t work. There are an overwhelming number of cable brands out there. No way you can audition all the possible permutations - even staying within a narrow price range. If not liking the Cable Co.’s products, deal with others that will allow an in-home audition. There are lots of high value, affordable options out there. Abandon the delusion that you’ll be able to discover the Platonic Ideal for your exact system or that such even exists! (Oh, heresy!!). Don’t obsess too much. Enjoy the music. Good luck.

tritonmark  ,I firmly believe that cabling makes a difference,subtle and not so subtle. I have spent hours swapping out cables back in the day( i had access to many ).I prefer to think of it this way,depending on your components and there quality there internal wires vary and  are higher grades.In my exerience i noticed the biggest difference between preamp and poweramps,  then components and  then speaker cable .I personnally saw massive changes in the distance of the run ,like a 20ft run will operate or work better with a better cable(try it with cheap speaker chord ) imo .short distance is less noticable, within reason providing you are using a decent wire.10k on a speaker cable?? well ya better have a pair of 75k plus speakers imo .Diffferent cables do sound different and are more lush or warmer then others some are flat.To me the key is what does your setup need to accent it .Is your room bright?speakers? But  isn't the goal to be uncolored, that's what we are shooting  to recreate "The original recording"  just my opinion, i would not shutter to spend 10-15% on cabling of my systems total investment.. more then that i am on the fence ...and remember new cables require burn in to sound at there best.

I second stringreen's comment, I've found power cords to make the largest difference, then, for me, it's a tie between the speaker, interconnect and cables.
Also I second ghosthouse's comment, don't listen to us, reviews, audioholic bloggers, get your hands on a few different cables and listen.  I would not say cables are subtle, but I agree that the speakers are first, and electronics second, but the cables are right there too.  Listen to a few cables with your ears...you'll find which one works the best for your system.