Try building both types of telesope Reflector or refractor. I`ve constructed both styles over the years and each presents it`s own set of problems for you to deal with. I`d get a hold of the Edmund Scientific Co. book on Home built telescopes (They have a web site.) for lots of useful & cheap ideas on building scopes and mounts. Some of the material is dated but there is nothing I have found so useful since I began playing around with optics in the early 1960`s.
If you`re planning on planetary observation, build a refractor using the best objective you can afford preferably 90mm or larger and f15 or greater. A telescope of these dimensions is akward to haul but the image quality usually is much superior to newtonians or cats unless they are of the very finest (read expensive) quality.