Just saw this thread and thought I'd add my two cents based not from personal experience, but from a family member who did this upon retirement.
Chickens are a great way to get started on livestock. Just make sure the coop is predator tight at night. You also have to open the coop in the mornings and lock it at night. This has the drawback that someone always has to be there to take care of things, so that cuts down on vacations away from home. After a while what this family member did was build a shelter completely covered in chicken wire, and put in an automated door opener/closer on a timer. That meant they could spend the night somewhere and not have to worry too much, but it's not something you leave for a week.
6-8 chickens are a good starting spot, plenty of eggs, probably more than you can eat, and not too much maintenance apart from what I said above. It's also relatively easy to increase the number if you want. And free range chicken that you raise yourself tastes fucking amazing!
Larger livestock such as pigs and/or goats you should not get into until after a year or two of chicken raising. By that time you know if you're into it or not, and if you find half a dozen chickens a chore, don't go for anything larger. If, however, you like it, try out a pair.
On of the best things you can do is to get to know your neighbours. Chances are they have been doing shit like this for longer than you and have some good tips. Farming communities also tend to become tight-knit and help each other out. Makes both for a great sense of community (if you're lucky to have a good farming community) and can save you a lot of time and money by teaching and helping you do shit. I think this is actually what my family member enjoys most out of this, the communal aspect.
You may want to think long term with regards to crop farming. If you have the space, plant some berry bushes, and some fruit trees. Sure, they won't give you anything for a few years, but after that it's great. My family member bought their homestead complete with apple, peach and cherry trees, as well as some large berry bushes. Autumns = fresh fruit for snacks and desert every day, and the winters are spent eating the copious amounts of preserves and jams. And apart from a few hard days work in the autumn, (and possibly while growing if you plant them young), they take care of themselves. You may also want to think of planting some hops if you intend on homebrewing beer.
Potatoes, beets and other root vegetables are also relatively low maintenance, and well worth it. Well worth digging into info on multi-year crops such as beans and peas too.
Homesteading is awesome, for those who like it, but it will sap all your spare time from you. Don't underestimate it, but as I say, if you like it, go for it.