Q: Besides Rope and Impact Toys, what other toys do people commonly collect?
So many things!  Here are some!
Impact Toys:  Floggers (Finger, 50 Falls, 100 Falls,  9-Tails),  Paddles (Wood, Plastic, Heavy), Crops, Dragontails, Switches, Canes
Collars: Day Collars, Play Collars, Choking Collars,  Roleplay Collars, Fur Collars, Pride Collars, Ownership Collars
Outfits: Leather, Latex, Zentai, Fur, Costumes, Corsets, Hosiery
Sensory Deprivation Items: Hoods, Blindfolds, Masks, Paws, Armbinders, Gags
Knives: Metal, Resin, Wood, Recurve Blades, Daggers, Hunting Knives, Folding Knives, Butterfly
Other Wearables: Ears, Nails, Claws

Q: I really like this toy... does that mean I have a fetish?

Possibly!  But don't worry about the definition.  The important part to this perspective is that Toys tend to be a key part of your kink activity, or that you tend to enjoy kink activity that involves a particular toy.  One thought to branch out your play is to use the toy as an augmentation to a scene, instead of the focus of your play.  For example, if you like using a violet wand, try doing a Mad Scientist scene, and your partner can be your Kinky Lab Assistant.  If you're into Impact, do an interrogation scene with your partner, where they have a secret and you try to "force" it out of them.

Q: How do I safely try out new toys, or bigger toys like sex furniture?

Usually local dungeons, play parties, or certain classes offer opportunities to try out these options.  The etiquette for most of these parties is similar to a gym... clean the equipment before you use it, clean the equipment after you use it, and make sure everything is put away neatly when you are done.  Often to attend a party that would have these options, you need to be "vetted" by attending local munches, being a positive part of the community, and making friends with your local kinksters.

Q: Where do you buy your toys / how expensive are your toys?

Toys can fit a wide range of budgets and playstyles.  For example, a simple ribbon around the neck can make an excellent collar... but you can also buy collars that cost hundreds of dollars and have everything from custom tooled leather to embedded precious stones.  Etsy used to be the premiere option, but has since cracked down on kink sellers.  If you can find an Etsy seller who has what you want, they are often small businesses that can serve your needs, work with you to get exactly what you want, and have a lot of more practical options for sizing than even specialty adult stores like Adam&Eve.  Other than that, vendors at kink events often have a good selection and are sometimes willing to take commissions for special toy orders.