As for pricing, your suggestion of $20,000 x 98 seems high for a sliver of road frontage to add a turn lane. Granted, you have the right to try to sell your property for whatever you think it is worth (unless it is a government taking for market value, or if you just don’t own the property in the first place), but that does not mean someone will buy it if it is overpriced. The developer likely has other options. Usually valuations in a situation like this are based on an appraised (or negotiated) value per acre or square foot, and then a survey determines the precise size of the sliver of land that is being conveyed at that rate.
Use a title company if you are not familiar with deeds, deed conveyance and closing of real estate. I prefer First American Title and you can find them anywhere. They will handle the monies, title search, title policy, deed, recording of the deed and pro-rated taxes, etc. Fees will vary and you can certainly negotiate. Typically the seller pays for the title policy and the buyer pays for half of the escrow fees. You can always charge an extra recording fee to offset these expenses.
Even though Craigslist is clearly the winner in terms of traffic, it's not necessarily the most versatile medium. There are plenty of restrictions in place (like the inability to link to third-party websites and embed videos), however with the tools that are available – it's more than enough to inform buyers about what the property has to offer and drum up enough interest to generate some legitimate leads and sales.
Pricing land can be trickier when compared to pricing a home. Developed lots in communities may have a clear “market” price based on the recent sale of similar lots. Raw land, however, may have fewer “comparable” sales to use in determining your price. In addition, the price you ultimately can attract for a singular lot or undeveloped land can vary greatly depending on the buyer’s intended use of the property. For example, if a buyer feels that your acreage is appropriate for a high-end home development it likely will bring a higher price per acre than if a buyer only intends to build a single home on it.
Hire an appraiser to determine the value of your land if you don't have the market knowledge to do it yourself. Without knowing what your land is worth, it will be hard for you to assess the strength of the offers that you receive. The appraisal will also determine the highest and best use of the land, and you can use that information to target your marketing activities.
Consider your own needs when pricing, and understand how pricing could impact buyers’ interest. When selling real estate, you sometimes have to choose between getting the highest price and possibly selling quicker. Plus, your pricing may be influenced if you need to sell for financial reasons. In addition to your own situation, pricing your property ultimately requires an understanding of the land market as a whole, why people are buying lots or land in that area and who these people are. A good real estate agent with land expertise can help greatly in this process.