One of the best places to purchase unopened hobby boxes of baseball cards is through online sports card retailers and auction websites. There are several reputable online retailers that sell new and sealed hobby boxes from the current and recent baseball card seasons. Some top options to consider include:

Steel City Collectibles: This site has been in business for over 20 years and offers a wide selection of all the major baseball card releases from Topps, Panini, Leaf, etc. They guarantee authentic products still sealed in the factory wrap. Free shipping is available on orders over $75.

DaCards: Another trusted retailer with a large inventory of new baseball card boxes and packs. DaCards has competitive prices and fast shipping. They also sell individual cards, magazines, supplies and accessories if you want to build your whole collection through one site.

BlowoutCards: Known industry-wide as one of the biggest sports card retailers. BlowoutCards stocks every major brand and release. You can find older/vintage boxes too for collecting older sets. They also grade and authenticate cards through their in-house service if needed.

Steele Sports Cards: Operating since 1998, Steele offers great prices on new release baseball boxes as well as supplies, memorabilia and older wax packs/boxes. Their site layout makes it easy to browse current products too.

eBay: The largest online auction marketplace. By using eBay, you have access to collectibles being sold by thousands of hobby shops, dealers and collectors worldwide. Make sure to thoroughly check seller feedback/history before bidding on expensive boxes. Many authentic and sealed vintage boxes can be found for lower prices than retail sites by using eBay’s auction format.

COMC (Cardboard Connection): Primarily an online marketplace for buying and selling individual sports cards. However, COMC also lists unopened hobby boxes and case breaks for sale from verified dealer stores. Their condition grading service provides an extra layer of confidence in box/pack quality.

In addition to online retailers, your local card shop is another good place to check for newly released hobby boxes before they sell out of stock. Stopping by LCS’s (local card shops) allows you to inspect boxes in-person before buying. They may offer bundle/case discounts not available elsewhere too. Be aware smaller shops have limited supplies compared to large online stores.

Whether buying from a local shop or website, there are several factors worth considering when choosing between hobby boxes:

-Brand/Set – Topps, Panini and Upper Deck are the major baseball producers. Consider the specific set, player roster, design and chase cards included. High-end sets have best odds at rare autographs and memorabilia.

-Release Year – Current/last season usually have best resell value. Older classic sets gain appeal years later potentially. Vintage boxes before 1990 are true collecting investments.

-Box Contents – Hobby boxes on average contain 10-20 packs each with multiple trading cards. Jumbo/mega boxes deliver more packs/hits per box. Breakers sell spots in expensive full case breaks too.

-Box Condition – Newly shipped hobby boxes are factory sealed in protective wrap. Pre-owned boxes may have resealed packs posing authenticity concerns despite lower price. Always buy from trusted sources.

-Prices – Box MSRP ranges between $70-350 usually but can spend $500+ on high-end releases. Online shops have best combination of inventory, competitive prices and customer service satisfaction.

With the wide variety of options between online retailers, auction sites and local shops, discerning collectors have many reliable ways to purchase unopened baseball card hobby boxes depending on budget, set preferences and collecting goals. Purchasing freshly packed boxes with team logos still crisp helps collectors build complete rainbow sets or target chase cards with improved odds versus loose packs. Following the tips above will lead to many enjoyable experiences opening wax in search of your next prized rookie card pull. Let me know if you need any other recommendations!