recently when i took my practice test i felt i was really slow too, my problem is the SC cause i will sit and gaze at it forever...the only answer for that (of what i hear from the grapevine) is doing alot of SC and timing your self while you do it.
For the Reading Comps, someone who took the Manhattan GMAT
course actually told me to perfect the art of Skimming (I know many may disagree with this technique-alot of LSAT people think i am mad) but if you chart out in diagrams a process of mapping key things (that always seem to be asked) then you will in time be good to go.
I usually map Assumptions, Tone, Objective [there may be others but usually those are detail specific]
At first i almost took 20 minutes per Read... but after awhile i didnt even need to do the diagrams, they were in my head. Now i automatically look for them. Yesterday i finished both my read sections in 10 minutes flat and got em right.
This may not work for you but trust me trying it will do you no harm. Also it speeds up your reading ability [and i know cause i read really slowly, struggled on the SAT with it also]
Tell me how it goes, and if anyone feels i may be wrong about something do post it, so i can hone my technique too