Learn Hardcore Japanese: syoten ha eki no tikaku ni arimasu.

The particle は marks 書店 as the topic (“As for the bookstore…”), setting the context for what you’re going to say about it (its location). If you used が, you’d simply be stating the existence of the bookstore near the station without making it the topic.
Example with が:
書店が駅の近くにあります。 → “There is a bookstore near the station.” (neutral announcement)
With は:
書店は駅の近くにあります。 → “As for the bookstore, it’s near the station.” (we’re talking about the bookstore’s whereabouts)

What’s the function of の in 駅の近く?

The particle の links two nouns, showing a relationship similar to the English possessive or “of.” Here, 駅の近く literally means “the vicinity of the station” or “station’s nearby area.”

Why is there a に after 近く?

The particle に marks the location where something exists or occurs when used with the verbs ある/あります or いる/います. So 駅の近くにあります means “(it) exists in/at the station’s vicinity.”

Why do we use あります instead of いる?

Japanese uses ある/あります for the existence of inanimate objects (like bookstores, books, cars). いる/います is for animate beings (people, animals). Since a bookstore is inanimate, you use あります.

Is this sentence formal or casual?

Because it ends in 〜ます (あります), it’s in the polite register. In casual speech, you would use the plain form ある:
書店は駅の近くにある。

Can I reorder it as 駅の近くに書店があります? Does that change the meaning?

Yes, you can. Japanese word order is flexible. Starting with 駅の近くに shifts the emphasis to the location (“Near the station, there is a bookstore”). The overall meaning stays the same, but you’re foregrounding the place rather than the bookstore.

What does 近く mean, and can I use 近い instead?

近く is a noun meaning “vicinity” or “proximity.” 近い is an adjective meaning “near” or “close.” If you want to use 近い to modify 書店, you’d say:
駅に近い書店があります。 → “There is a bookstore close to the station.”

How do I ask “Where is the bookstore?” using this pattern?

You can say:
書店はどこにありますか？
Literally, “As for the bookstore, at where does it exist?”
Answer: 駅の近くにあります。 (“It’s near the station.”)

Can particles like は or に ever be dropped to sound more casual?

In very casual or spoken Japanese you might drop particles for brevity, especially among friends. For example:
駅の近くに書店あるよ。
But be aware that dropping particles can make your speech unclear or sound too informal in many contexts.

Why isn’t there an English article like “the” or “a” in the sentence?

Japanese doesn’t use articles the way English does. Definiteness and indefiniteness (the vs. a) are usually determined by context rather than specific words. Here, 書店 simply means “a bookstore” or “the bookstore” depending on what’s already known in the conversation.