There are 192 Pokemon cards with 30 HP, plus the Lillie's Poké Doll and Robo Substitute Trainer cards. This list is too long for Pokebase; it may be accessed here.
Though 30 HP is the lowest any Pokemon card goes, two Trainer cards can be played like Pokemon and have 10 HP. These are the Base Set's Clefairy Doll and the Fossil set's Mysterious Fossil.
HP (Bulbapedia)
http://www.pokemon.com/us/pokemon-trading-card-game/database/advanced/?cardName=&cardText=&basic-pokemon=&evolvesFrom=&format=unlimited&hitPointsMin=0&hitPointsMax=30&retreatCostMin=0&retreatCostMax=5&totalAttackCostMin=0&totalAttackCostMax=10&particularArtist=&searchDatabase=Search Database&sort=Position
those are all of em! because the LOWEST Pokemon card HP is 30. and there are alot of magicarp and baby Pokemon! =P
The card with the lowest HP would actually be the early Mysterious Fossils. http://serebii.net/card/fossil/062.shtml 10 HP as you can see.