Swim Speed Potions (used especially at lvl 37 for Faldir's Cove in Arathi Highlands and lvl 57 in WPL). Try to get multiple stacks of these. I also recommend keeping a stack of these always in your bags. You will frequently pass rivers and lakes and can use these potions to pass them faster through out the guide. Please note that these potions do not stack with Druid's Aquatic Form and Glyph of Aquatic Form.
Galakrond-Alliance-USGalakrond-H-USGallywix-Alliance-USGallywix-Horde-USGarithos-Alliance-USGarithos-Horde-USGarona-Alliance-USGarona-Horde-USGarrosh-Alliance-USGarrosh-Horde-USGhostlands-Alliance-USGhostlands-Horde-USGilneas-Alliance-USGilneas-Horde-USGnomeregan-Alliance-USGnomeregan-Horde-USGoldrinn-Alliance-USGoldrinn-Horde-USGorefiend-Alliance-USGorefiend-Horde-USGorgonnash-Alliance-USGorgonnash-Horde-USGreymane-Alliance-USGreymane-Horde-USGrizzly Hills-Alliance-USGrizzly Hills-Horde-USGul'dan-Alliance-USGul'dan-Horde-USGundrak-Alliance-USGundrak-Horde-USGurubashi-Alliance-USGurubashi-Horde-US
Keep in mind that these quests are optional, and are not necessary to continue leveling and capturing companions. They are also account-wide, so if you complete the quest chain on one character, you will not be able to complete it again on another. However, any progress that you've made will be saved and you can pick up where you left off in the quest chain on another character. The dailies that you've unlocked will also be accessible by all your toons.
Thanks so much for the replies. I think I am somewhat of a collector/roster builder. I go around doing the dailies but I also like buying pets just for their looks. I watched hazelnutty on youtube last night. I think I will focus on doing the expeditions when I have time to get all the pets that come from that. Then I will go back and do old raids like Eekwibble suggested.
Go to https://www.tradeskillmaster.com/pets/compare to compare prices of different servers. I’ve done this a lot, and I’ve bought pets for a few hundred gold on a server, transferred it to my main server and sold for 10k gold and more. You also need to buy cheap pets on your main server to transfer to other servers so that you can build up a bit of gold on other servers so that you can buy pets.