Bassman,
Deoends what your fishing for where it pertains to leaders.
do you want to tie your own? Some would argue that hand tied leaders perform the best.If so get a leader kit,Flyfisher's Paradise in State College sells one also come with directions for various leaders and explanation of leaders,as well as formulas.
IMHO Maxima In Chameleon or Ultragreen is a great leader butt and midsection material.For tippets i have found Rio Powerflex a great new discovery for me,prior to that i have used orvis Super Strong,ClimaxMaxima Ultragreen as well as cortland mono for tippets .This as listed is standard fare for dry fly leaders.
In the Past folks used silk for leaders,then after the advent of WW2 nylon was discovered and soon leaders and tippet were made of this for a good many years ,like silk this was all that was available for a while,in the meantime mono became better and better,and then Florocarbon became available.
Flourocarbon is better suited to Wetflies,Softhackles,Nymphs,and Streamers.In the Saltwater scene Flourocarbon is the standard leader material and tippet material.
Saltwater Regulars will tell you flat out Seaguar is the best,where it perrtains to flourocarbon they invented it they brought it to market and they have improved it too.Also Froghair has done some work to improve through their Gamma technology.
For freshwater dry fly fishing leaders with maxima butts and midsections and Rio Flouroflex perform hands down.Other mono i'd use for tippet is Orvis Super Strong it also very very good.
For Nymphing /wets/softhackles use Maxima for butts and mid sections,use flouro Seaguar Grandmax,And Rio Floroflex plus for tippets.for streamers since the leader is generally shorter use Flouro through and through usually just three sections to a streamer leader till yer at the fly.
Saltwater Flourocarbon only,Seaguar is the standard and the best ,maybe some fine coated knotable wire leader for tippet when blues or toothy critter are around, also works for musky and pike fishing too.
Tight Wraps & Tight Lines
Rick Wallace