How hard is it to build bookshelves?

A good book, patience, and lots of wood and a smart/crafty person can DIY. It might be cheaper / faster / more enriching for you to post on craigslist and ask if there is a local hadyman-type that would be willing to teach you as you do the project together on-site. This way, you get what you want accomplished and you learn from the experience—it will probably cost less than you are fearing, and you will be helping our your local craftsman.

carpentry is a skilled craft that takes years to master. The proper tools are key. U will spend just about the same in wood and materials ( that is if you do not make many mistakes) than u would if you purchased at a ikea or similar store. I dabble and some
etimes its passable sometimes its a wreck, but most times it does not look proffesional. I am getting better. Try your hand at buying something used and refinishing it. Its takes less money time and skill, but it is rewarding none the less.

It is very easy if you know what you’re doing. If not, then you will have amateur results that may be less than satisfactory. If you’re fine with that, go for it. Does someone actually need to tell you this?

They are easy to build, but they are hard to build well. I am a carpenter and have had to tear out other peoples attempts and rebuild them right. It depends on the tools and experience you have. Good bookshelves should last a lifetime. You can buy decent ones for a fair price, or pay to have exactly what you want built for you.